diff --git a/README.md b/README.md
index 2328b6340..692550356 100644
--- a/README.md
+++ b/README.md
@@ -13,14 +13,14 @@ The [contributing documentation](CONTRIBUTING.md) covers licencing and the usual
 
 [Cincinnati][] is configured to track the master branch, so it will automatically react to updates made to this repository.
 
-### Schema version
+### Schema Version
 
 The layout of this repository is versioned via [a `version` file](version), which contains the [Semantic Version][semver] of the schema.
 As a schema version, the patch level is likely to remain 0, but the minor version will be incremented if backwards-compatible features are added, and the major version will be incremented if backwards-incompatible changes are made.
 Consumers, such as [Cincinnati][], who support *x.y.0* may safely consume this repository when the stated major version matches the understood *x* and the stated minor version is less than or equal to the understood *y*.
 For example, a consumer that supports 1.3.0 and 2.1.0 could safely consume 1.2.0, 1.3.0, 2.0.0, 2.1.0, etc., but could not safely consume 1.4.0, 2.2.0, 3.0.0, etc.
 
-### Release names
+### Release Names
 
 Release names are used for [adding releases to channels](#add-releases-to-channels) and [blocking edges](#block-edges).
 Architecture-agnostic names will apply to all images with that exact name in the `version` property of the `release-metadata` file included in the release image.
@@ -31,13 +31,60 @@ And 4.2.14+amd64 would only apply to the amd64 release image.
 ### Add Releases To Channels
 
 Edit the appropriate file in `channels/`.
-For example, to add a release to stable-4.2 you would edit `channels/stable-4.2.yaml`.
-Channel semantics are documented [here][channel-semantics].
+For example, to add a release to candidate-4.2 you would edit [`channels/candidate-4.2.yaml`](channels/candidate-4.2.yaml).
 
 The file contains a list of versions.
 Please keep the versions in order.
 And LEAVE COMMENTS if you skip a version.
 
+#### Feeder Channels
+
+Channel semantics, as documented [here][channel-semantics], show nodes and edges being promoted to successive channels as they prove their stability.
+For example, a 4.2.z release will appear in `candidate-4.2` first.
+Upon proving itself sufficiently stable in the candidate channel, it will be promoted into `fast-4.2`.
+Some time after landing in `fast-4.2`, it will appear in `stable-4.2`.
+
+_Note:_ Once we have phased release rollouts, we will drop the fast/stable distinction from this repository and promote to a unified fast/stable channel with a start time and rollout duration.
+Until then, we are using fast channels to feed stable channels with a delay, just like candidate channels feed fast channels.
+
+In this repository, the intended promotion flow is reflected by a `feeder` property in the channel declaration.
+For example, for [`channels/fast-4.2.yaml`](channels/fast-4.2.yaml):
+
+```yaml
+feeder:
+  name: candidate-4.2
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*|\+amd64|-s390x)?
+```
+
+which declares the intention that nodes and edges will be considered for promotion into `fast-4.2` after cooking for one week in `candidate-4.2`.
+The `delay` value is an [ISO 8601][rfc-3339-p13] [duration][iso-8601-durations].
+The `filter` value excludes `4.2.0-rc.5` and other releases, while allowing for `4.2.0-0.hotfix-2020-09-19-234758` and `4.2.10-s390x` and `4.2.14+amd64`.
+
+This is the expected delay, but it does not mean that promotion will happen at that moment.
+For example, it is possible that release architects decide that there is insufficient data for a `fast-4.2` promotion, in which case the promotion can be delated until sufficient data accumulates.
+
+To see recommended feeder promotions, run:
+
+```console
+$ hack/stabilization-change.py
+```
+
+##### Tombstones
+
+Removing a node from a channel can strand existing clusters with a `VersionNotFound` error.
+To avoid that, unstable nodes are left in their existing channels, but should not be promoted to additional channels.
+This is reflected through entries in the optional `tombstones` property.
+For example, [`channels/candidate-4.2.yaml`](channels/candidate-4.2.yaml) has:
+
+```yaml
+tombstones:
+- 4.1.18
+- 4.1.20
+```
+
+declaring that, while 4.1.18 and 4.1.20 are in `candidate-4.2`, they should not be promoted to subsequent channels (in this case, `fast-4.2`).
+
 ### Block Edges
 
 Create/edit an appropriate file in `blocked_edges/`.
@@ -59,5 +106,7 @@ from: 4\.1\.(18|20)
 [channel-semantics]: https://docs.openshift.com/container-platform/4.3/updating/updating-cluster-between-minor.html#understanding-upgrade-channels_updating-cluster-between-minor
 [Cincinnati]: https://github.com/openshift/cincinnati/
 [image-arch]: https://github.com/opencontainers/image-spec/blame/v1.0.1/config.md#L103
+[iso-8601-durations]: https://en.wikipedia.org/wiki/ISO_8601#Durations
+[rfc-3339-p13]: https://tools.ietf.org/html/rfc3339#page-13
 [semver]: https://semver.org/spec/v2.0.0.html
 [semver-build]: https://semver.org/spec/v2.0.0.html#spec-item-10
diff --git a/channels/candidate-4.2.yaml b/channels/candidate-4.2.yaml
index 2d218a5d0..aebb75098 100644
--- a/channels/candidate-4.2.yaml
+++ b/channels/candidate-4.2.yaml
@@ -1,4 +1,13 @@
 name: candidate-4.2
+tombstones:
+- 4.1.18
+# no 4.1.37 because of https://bugzilla.redhat.com/show_bug.cgi?id=1810393 (Jenkins webconsole 403 Forbidden)
+- 4.1.37
+- 4.2.14
+# no 4.2.30 because broken build causing machine-api-operator CrashLoopBackoff, https://bugzilla.redhat.com/show_bug.cgi?id=1829028
+- 4.2.30
+# no 4.2.32 because of RHEL 8.2 ICMP, https://bugzilla.redhat.com/show_bug.cgi?id=1781575
+- 4.2.32
 versions:
 - 4.1.18
 - 4.1.20
diff --git a/channels/candidate-4.3.yaml b/channels/candidate-4.3.yaml
index 99d75a1b0..cd3b6b8e0 100644
--- a/channels/candidate-4.3.yaml
+++ b/channels/candidate-4.3.yaml
@@ -1,4 +1,21 @@
 name: candidate-4.3
+tombstones:
+# no 4.2.30 because broken build causing machine-api-operator CrashLoopBackoff, https://bugzilla.redhat.com/show_bug.cgi?id=1829028
+- 4.2.30
+# no 4.2.32 because of RHEL 8.2 ICMP, https://bugzilla.redhat.com/show_bug.cgi?id=1781575
+- 4.2.32
+# No 4.3.11 because of build issues: https://bugzilla.redhat.com/show_bug.cgi?id=1823378
+- 4.3.11
+# No 4.3.14 (did not include 4.3.0 as an update source: https://github.com/openshift/cincinnati-graph-data/pull/194#issuecomment-618080792 )
+- 4.3.14
+# No 4.3.15 (did not include DefaultSecurityContextConstraints_Mutated clear: https://bugzilla.redhat.com/show_bug.cgi?id=1827337 )
+- 4.3.15
+# No 4.3.16 (OVN container has unsigned RPMs: https://github.com/openshift/cincinnati-graph-data/pull/205#issuecomment-619049150 )
+- 4.3.16
+# No 4.3.17 because of CRI-O OCINI context, https://bugzilla.redhat.com/show_bug.cgi?id=1828104
+- 4.3.17
+# No 4.3.24, because we were minimizing Quay load
+- 4.3.24
 versions:
 - 4.2.36
 - 4.2.34
diff --git a/channels/candidate-4.4.yaml b/channels/candidate-4.4.yaml
index c0ba0a9ae..717bd0ec8 100644
--- a/channels/candidate-4.4.yaml
+++ b/channels/candidate-4.4.yaml
@@ -1,4 +1,46 @@
 name: candidate-4.4
+tombstones:
+# No early 4.3.z will be promoted to fast, these are just for testing -> RC updates
+- 4.3.5
+- 4.3.8
+- 4.3.9
+- 4.3.10
+# No 4.3.11 because of build issues: https://bugzilla.redhat.com/show_bug.cgi?id=1823378
+- 4.3.11
+# No 4.3.14 (did not include 4.3.0 as an update source: https://github.com/openshift/cincinnati-graph-data/pull/194#issuecomment-618080792 )
+- 4.3.14+amd64
+# No 4.3.15 (did not include DefaultSecurityContextConstraints_Mutated clear: https://bugzilla.redhat.com/show_bug.cgi?id=1827337 )
+- 4.3.15+amd64
+# No 4.3.16 (OVN container has unsigned RPMs: https://github.com/openshift/cincinnati-graph-data/pull/205#issuecomment-619049150 )
+- 4.3.16
+# No 4.3.17 because of CRI-O OCINI context, https://bugzilla.redhat.com/show_bug.cgi?id=1828104
+- 4.3.17+amd64
+# No 4.3.24, because we were minimizing Quay load
+- 4.3.24
+# RC releases are never promoted to fast channels
+- 4.4.0-rc.0
+- 4.4.0-rc.1
+- 4.4.0-rc.2
+- 4.4.0-rc.4
+- 4.4.0-rc.6
+- 4.4.0-rc.7
+- 4.4.0-rc.8
+- 4.4.0-rc.9
+- 4.4.0-rc.10
+- 4.4.0-rc.11
+- 4.4.0-rc.12
+- 4.4.0-rc.13
+# No 4.4.0 because MachineConfig CRD does not define all fields which users might have set in 4.3, https://bugzilla.redhat.com/show_bug.cgi?id=1829651
+- 4.4.0
+# No 4.4.2 because 4.4 MachineSet with 4.2 or earlier bootimages fails to scale up because old CRI-O chokes on new CRI-O config, https://bugzilla.redhat.com/show_bug.cgi?id=1830102
+- 4.4.2
+# No 4.4.7, because we were minimizing Quay load
+- 4.4.7
+# Shares an errata with a later release
+- 4.4.22
+- 4.4.24
+- 4.4.25
+- 4.4.28
 versions:
 - 4.3.40
 - 4.3.38
diff --git a/channels/candidate-4.5.yaml b/channels/candidate-4.5.yaml
index ada3c2fa3..27a2f6283 100644
--- a/channels/candidate-4.5.yaml
+++ b/channels/candidate-4.5.yaml
@@ -1,4 +1,22 @@
 name: candidate-4.5
+tombstones:
+# No 4.4.0 because MachineConfig CRD does not define all fields which users might have set in 4.3, https://bugzilla.redhat.com/show_bug.cgi?id=1829651
+- 4.4.0
+# No 4.4.2 because 4.4 MachineSet with 4.2 or earlier bootimages fails to scale up because old CRI-O chokes on new CRI-O config, https://bugzilla.redhat.com/show_bug.cgi?id=1830102
+- 4.4.2
+# No 4.4.7, because we were minimizing Quay load
+- 4.4.7
+# Never got an errata
+- 4.5.0-0.hotfix-2020-11-28-021842
+# Shares an errata with a later release
+- 4.4.22
+- 4.4.24
+- 4.4.25
+- 4.4.28
+- 4.5.0
+- 4.5.25
+- 4.5.29
+- 4.5.32
 versions:
 - 4.4.33
 
diff --git a/channels/candidate-4.6.yaml b/channels/candidate-4.6.yaml
index 2c4feb28a..773703481 100644
--- a/channels/candidate-4.6.yaml
+++ b/channels/candidate-4.6.yaml
@@ -1,4 +1,22 @@
 name: candidate-4.6
+tombstones:
+# Never got an errata
+- 4.5.0-0.hotfix-2020-11-28-021842
+# Shares an errata with a later release
+- 4.5.0
+- 4.5.25
+- 4.5.29
+- 4.5.32
+- 4.6.0
+- 4.6.2
+# Rerolling as 4.6.6 with a rebuilt CRI-O RPM
+- 4.6.5
+# Blocked on born-in-4.1 ingress regression: https://bugzilla.redhat.com/show_bug.cgi?id=1904582#c4
+- 4.6.7
+# Did not fix 4.6.9 OVS regression https://bugzilla.redhat.com/show_bug.cgi?id=1914284
+- 4.6.10
+# 4.6.24 introduced a regression in registry ca-trust handling: https://bugzilla.redhat.com/show_bug.cgi?id=1949040#c4
+- 4.6.24
 versions:
 - 4.5.37
 
diff --git a/channels/candidate-4.7.yaml b/channels/candidate-4.7.yaml
index 07297d428..f5301c9f1 100644
--- a/channels/candidate-4.7.yaml
+++ b/channels/candidate-4.7.yaml
@@ -1,4 +1,9 @@
 name: candidate-4.7
+tombstones:
+# Did not fix 4.6.9 OVS regression https://bugzilla.redhat.com/show_bug.cgi?id=1914284
+- 4.6.10
+# 4.6.24 introduced a regression in registry ca-trust handling: https://bugzilla.redhat.com/show_bug.cgi?id=1949040#c4
+- 4.6.24
 versions:
 - 4.6.25
 
diff --git a/channels/eus-4.6.yaml b/channels/eus-4.6.yaml
index 699149dc9..24d39b3f6 100644
--- a/channels/eus-4.6.yaml
+++ b/channels/eus-4.6.yaml
@@ -1,4 +1,8 @@
 name: eus-4.6
+feeder:
+  name: stable-4.6
+  delay: PT0H
+  filter: 4\.6\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.6.1
 - 4.6.3
diff --git a/channels/fast-4.2.yaml b/channels/fast-4.2.yaml
index 5f9f6f64f..a626dd569 100644
--- a/channels/fast-4.2.yaml
+++ b/channels/fast-4.2.yaml
@@ -1,4 +1,10 @@
 name: fast-4.2
+feeder:
+  name: candidate-4.2
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*|\+amd64|-s390x)?
+tombstones:
+- 4.2.10-s390x
 versions:
 - 4.1.20
 - 4.1.21
diff --git a/channels/fast-4.3.yaml b/channels/fast-4.3.yaml
index cfdfef419..370a1306d 100644
--- a/channels/fast-4.3.yaml
+++ b/channels/fast-4.3.yaml
@@ -1,4 +1,8 @@
 name: fast-4.3
+feeder:
+  name: candidate-4.3
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.2.36
 - 4.2.34
diff --git a/channels/fast-4.4.yaml b/channels/fast-4.4.yaml
index ae68f6897..8260e3ee3 100644
--- a/channels/fast-4.4.yaml
+++ b/channels/fast-4.4.yaml
@@ -1,4 +1,8 @@
 name: fast-4.4
+feeder:
+  name: candidate-4.4
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.3.40
 - 4.3.38
diff --git a/channels/fast-4.5.yaml b/channels/fast-4.5.yaml
index 3bdb2c190..72bbdbd54 100644
--- a/channels/fast-4.5.yaml
+++ b/channels/fast-4.5.yaml
@@ -1,4 +1,8 @@
 name: fast-4.5
+feeder:
+  name: candidate-4.5
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.4.33
 
diff --git a/channels/fast-4.6.yaml b/channels/fast-4.6.yaml
index 4ca31355f..e6c7925c2 100644
--- a/channels/fast-4.6.yaml
+++ b/channels/fast-4.6.yaml
@@ -1,4 +1,8 @@
 name: fast-4.6
+feeder:
+  name: candidate-4.6
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.5.37
 
diff --git a/channels/fast-4.7.yaml b/channels/fast-4.7.yaml
index 08a83c49f..4fba731e5 100644
--- a/channels/fast-4.7.yaml
+++ b/channels/fast-4.7.yaml
@@ -1,4 +1,8 @@
 name: fast-4.7
+feeder:
+  name: candidate-4.7
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.6.23
 - 4.6.22
diff --git a/channels/fast-4.8.yaml b/channels/fast-4.8.yaml
new file mode 100644
index 000000000..aba3e3892
--- /dev/null
+++ b/channels/fast-4.8.yaml
@@ -0,0 +1,6 @@
+name: fast-4.8
+feeder:
+  name: candidate-4.8
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
+versions: []
diff --git a/channels/prerelease-4.1.yaml b/channels/prerelease-4.1.yaml
index a58801d7e..a4d2941d9 100644
--- a/channels/prerelease-4.1.yaml
+++ b/channels/prerelease-4.1.yaml
@@ -1,4 +1,7 @@
 name: prerelease-4.1
+tombstones:
+# no 4.1.37 because of https://bugzilla.redhat.com/show_bug.cgi?id=1810393 (Jenkins webconsole 403 Forbidden)
+- 4.1.37
 versions:
 - 4.1.0
 - 4.1.0-rc.0
diff --git a/channels/stable-4.1.yaml b/channels/stable-4.1.yaml
index e1a162fc6..6442cff7e 100644
--- a/channels/stable-4.1.yaml
+++ b/channels/stable-4.1.yaml
@@ -1,4 +1,8 @@
 name: stable-4.1
+feeder:
+  name: prerelease-4.1
+  delay: P1W
+  filter: 4\.[0-9]+\.[0-9]+(.*hotfix.*)?
 versions:
 - 4.1.0
 - 4.1.1
diff --git a/channels/stable-4.2.yaml b/channels/stable-4.2.yaml
index 775898fcd..92e2963f9 100644
--- a/channels/stable-4.2.yaml
+++ b/channels/stable-4.2.yaml
@@ -1,4 +1,7 @@
 name: stable-4.2
+feeder:
+  name: fast-4.2
+  delay: PT48H
 versions:
 - 4.1.20
 - 4.1.21
diff --git a/channels/stable-4.3.yaml b/channels/stable-4.3.yaml
index e697e4a6e..7420f1d05 100644
--- a/channels/stable-4.3.yaml
+++ b/channels/stable-4.3.yaml
@@ -1,4 +1,7 @@
 name: stable-4.3
+feeder:
+  name: fast-4.3
+  delay: PT48H
 versions:
 - 4.2.36
 - 4.2.34
diff --git a/channels/stable-4.4.yaml b/channels/stable-4.4.yaml
index c8af4b890..2e823c77a 100644
--- a/channels/stable-4.4.yaml
+++ b/channels/stable-4.4.yaml
@@ -1,4 +1,7 @@
 name: stable-4.4
+feeder:
+  name: fast-4.4
+  delay: PT48H
 versions:
 - 4.3.40
 - 4.3.38
diff --git a/channels/stable-4.5.yaml b/channels/stable-4.5.yaml
index 3333ca774..2ff90392c 100644
--- a/channels/stable-4.5.yaml
+++ b/channels/stable-4.5.yaml
@@ -1,4 +1,7 @@
 name: stable-4.5
+feeder:
+  name: fast-4.5
+  delay: PT48H
 versions:
 - 4.4.33
 
@@ -37,7 +40,9 @@ versions:
 - 4.5.7
 - 4.5.8
 - 4.5.9
+- 4.5.10
 - 4.5.11
+- 4.5.12
 - 4.5.13
 - 4.5.14
 - 4.5.15
diff --git a/channels/stable-4.6.yaml b/channels/stable-4.6.yaml
index b5855255b..e63505a87 100644
--- a/channels/stable-4.6.yaml
+++ b/channels/stable-4.6.yaml
@@ -1,4 +1,7 @@
 name: stable-4.6
+feeder:
+  name: fast-4.6
+  delay: PT48H
 versions:
 - 4.5.36
 - 4.5.35
diff --git a/channels/stable-4.7.yaml b/channels/stable-4.7.yaml
index 048823a5d..332ed6746 100644
--- a/channels/stable-4.7.yaml
+++ b/channels/stable-4.7.yaml
@@ -1,4 +1,7 @@
 name: stable-4.7
+feeder:
+  name: fast-4.7
+  delay: PT48H
 versions:
 - 4.6.23
 - 4.6.22
diff --git a/channels/stable-4.8.yaml b/channels/stable-4.8.yaml
new file mode 100644
index 000000000..627b848b9
--- /dev/null
+++ b/channels/stable-4.8.yaml
@@ -0,0 +1,5 @@
+name: stable-4.8
+feeder:
+  name: fast-4.8
+  delay: PT48H
+versions: []
diff --git a/hack/stabilization-changes.py b/hack/stabilization-changes.py
new file mode 100755
index 000000000..dfc6247a9
--- /dev/null
+++ b/hack/stabilization-changes.py
@@ -0,0 +1,109 @@
+#!/usr/bin/env python
+
+import datetime
+import logging
+import os
+import re
+import subprocess
+
+import yaml
+
+
+logging.basicConfig(format='%(levelname)s: %(message)s')
+_LOGGER = logging.getLogger(__name__)
+_LOGGER.setLevel(logging.DEBUG)
+_ISO_8601_DELAY_REGEXP = re.compile('^P((?P<weeks>\d+)W)?(T(?P<hours>\d+)H)?$')
+_GIT_BLAME_COMMIT_REGEXP = re.compile('^(?P<hash>[0-9a-f]{40}) .*')
+_GIT_BLAME_HEADER_REGEXP = re.compile('^(?P<key>[^ \t]+) (?P<value>.*)$')
+_GIT_BLAME_LINE_REGEXP = re.compile('^\t(?P<value>.*)$')
+
+
+def parse_iso8601_delay(delay):
+    # https://tools.ietf.org/html/rfc3339#page-13
+    match = _ISO_8601_DELAY_REGEXP.match(delay)
+    if not match:
+        raise ValueError('invalid or unsupported ISO 8601 duration {!r}.  Tooling currently only supports P<number>WT<number>H for week and/or hour offsets')
+    weeks = int(match.group('weeks') or 0)
+    hours = int(match.group('hours') or 0)
+    return datetime.timedelta(days=7*weeks, hours=hours)
+
+
+def stabilization_changes(directory):
+    channels = {}
+    paths = {}
+    for root, _, files in os.walk(directory):
+        for filename in files:
+            if not filename.endswith('.yaml'):
+                continue
+            path = os.path.join(root, filename)
+            with open(path) as f:
+                try:
+                    data = yaml.load(f, Loader=yaml.SafeLoader)
+                except ValueError as error:
+                    raise ValueError('failed to load YAML from {}: {}'.format(path, error))
+            channel = data['name']
+            if channel in channels:
+                raise ValueError('multiple definitions for {}: {} and {}'.format(channel, paths[channel], path))
+            paths[channel] = path
+            channels[channel] = data
+    for name, channel in sorted(channels.items()):
+        if not channel.get('feeder'):
+            continue
+        feeder = channel['feeder']['name']
+        delay_string = channel['feeder']['delay']
+        delay = parse_iso8601_delay(delay=delay_string)
+        version_filter = re.compile('^{}$'.format(channel['feeder'].get('filter', '.*')))
+        feeder_data = channels[feeder]
+        unpromoted = set(feeder_data['versions']) - set(channel['versions']) - set(feeder_data.get('tombstones', {}))
+        candidates = set(v for v in unpromoted if version_filter.match(v))
+        if not candidates:
+            continue
+        promotions = get_promotions(paths[feeder])
+        now = datetime.datetime.now()
+        _LOGGER.info('considering promotions from {} to {} after {}'.format(feeder, name, delay_string))
+        for version in sorted(candidates):
+            promotion = promotions[version]
+            version_delay = now - promotion['committer-time']
+            if version_delay > delay:
+                _LOGGER.info('  recommended: {} ({})'.format(version, version_delay))
+                _LOGGER.debug('    {}: Promote {} to {}'.format(paths[name].rsplit('.', 1)[0], version, name))
+                _LOGGER.debug('    It was promoted the feeder {} by {} ({}, {}).'.format(feeder, promotion['hash'][:10], promotion['summary'], promotion['committer-time'].date().isoformat()))
+            else:
+                _LOGGER.info('  waiting: {} ({})'.format(version, version_delay))
+
+
+def get_promotions(path):
+    # https://git-scm.com/docs/git-blame#_the_porcelain_format
+    output = subprocess.check_output(['git', 'blame', '--first-parent', '--porcelain', path]).decode('utf-8')
+    commits = {}
+    lines = {}
+    for line in output.strip().split('\n'):
+        match = _GIT_BLAME_COMMIT_REGEXP.match(line)
+        if match:
+            commit = match.group('hash')
+            if commit not in commits:
+                commits[commit] = {'hash': commit}
+            continue
+        match = _GIT_BLAME_HEADER_REGEXP.match(line)
+        if match:
+            key = match.group('key')
+            value = match.group('value')
+            if key == 'committer-time':
+                commits[commit]['committer-time'] = datetime.datetime.fromtimestamp(int(value))
+            else:
+                commits[commit][key] = value
+            continue
+        match = _GIT_BLAME_LINE_REGEXP.match(line)
+        if not match:
+            raise ValueError('unrecognized blame output for {} (blame line {}): {}'.format(path, i, line))
+        lines[match.group('value')] = commit
+    promotions = {}
+    for line, commit in lines.items():
+        if line.startswith('- '):
+            version = line[2:]
+            promotions[version] = commits[commit]
+    return promotions
+
+
+if __name__ == '__main__':
+    stabilization_changes(directory='channels')