diff --git a/channels/candidate-4.4.yaml b/channels/candidate-4.4.yaml
index 1bb178a3b..28e87cda6 100644
--- a/channels/candidate-4.4.yaml
+++ b/channels/candidate-4.4.yaml
@@ -26,6 +26,13 @@ versions:
 - 4.3.9
 - 4.3.8
 - 4.3.5
+- 4.3.3
+- 4.3.2
+- 4.3.1
+- 4.3.0
+- 4.3.0-0.hotfix-2020-09-30-133631
+- 4.3.0-rc.0
+- 4.3.0-rc.3
 - 4.4.0
 - 4.4.0-rc.0
 - 4.4.0-rc.1
@@ -67,5 +74,4 @@ versions:
 - 4.4.27
 - 4.4.28
 - 4.4.29
-
 - 4.4.30
diff --git a/channels/candidate-4.5.yaml b/channels/candidate-4.5.yaml
index bb966b12b..ed04d667b 100644
--- a/channels/candidate-4.5.yaml
+++ b/channels/candidate-4.5.yaml
@@ -1,5 +1,5 @@
 name: candidate-4.5
-versions: 
+versions:
 - 4.4.30
 - 4.4.29
 - 4.4.28
@@ -23,7 +23,25 @@ versions:
 - 4.4.10
 - 4.4.9
 - 4.4.8
+- 4.4.7
 - 4.4.6
+- 4.4.5
+- 4.4.4
+- 4.4.3
+- 4.4.2
+- 4.4.0
+- 4.4.0-rc.0
+- 4.4.0-rc.1
+- 4.4.0-rc.10
+- 4.4.0-rc.11
+- 4.4.0-rc.12
+- 4.4.0-rc.13
+- 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
 - 4.5.0
 - 4.5.0-0.hotfix-2020-08-24-185832
 - 4.5.0-rc.1
@@ -50,7 +68,5 @@ versions:
 - 4.5.15
 - 4.5.16
 - 4.5.17
-
 - 4.5.18
-
 - 4.5.19
diff --git a/channels/candidate-4.6.yaml b/channels/candidate-4.6.yaml
index bbae2cb22..2f1c355b8 100644
--- a/channels/candidate-4.6.yaml
+++ b/channels/candidate-4.6.yaml
@@ -1,9 +1,7 @@
 name: candidate-4.6
 versions:
 - 4.5.19
-
 - 4.5.18
-
 - 4.5.17
 - 4.5.16
 - 4.5.15
@@ -21,8 +19,15 @@ versions:
 - 4.5.3
 - 4.5.2
 - 4.5.1
+- 4.5.1-rc.0
+- 4.5.0
 - 4.5.0-0.hotfix-2020-08-24-185832
-
+- 4.5.0-rc.1
+- 4.5.0-rc.2
+- 4.5.0-rc.4
+- 4.5.0-rc.5
+- 4.5.0-rc.6
+- 4.5.0-rc.7
 - 4.6.0
 - 4.6.0-fc.0
 - 4.6.0-fc.1
@@ -38,9 +43,6 @@ versions:
 - 4.6.0-rc.3
 - 4.6.0-rc.4
 - 4.6.1
-
 - 4.6.2
-
 - 4.6.3
-
 - 4.6.4
diff --git a/channels/fast-4.4.yaml b/channels/fast-4.4.yaml
index 2cfa44f62..342c3a431 100644
--- a/channels/fast-4.4.yaml
+++ b/channels/fast-4.4.yaml
@@ -17,6 +17,15 @@ versions:
 - 4.3.18
 - 4.3.13
 - 4.3.12
+- 4.3.10
+- 4.3.9
+- 4.3.8
+- 4.3.5
+- 4.3.3
+- 4.3.2
+- 4.3.1
+- 4.3.0
+- 4.3.0-0.hotfix-2020-09-30-133631
 - 4.4.3
 - 4.4.4
 - 4.4.5
@@ -39,5 +48,4 @@ versions:
 - 4.4.26
 - 4.4.27
 - 4.4.29
-
 - 4.4.30
diff --git a/channels/fast-4.5.yaml b/channels/fast-4.5.yaml
index 5d7ec44a8..59320c4c7 100644
--- a/channels/fast-4.5.yaml
+++ b/channels/fast-4.5.yaml
@@ -1,7 +1,6 @@
 name: fast-4.5
 versions:
 - 4.4.30
-
 - 4.4.29
 - 4.4.27
 - 4.4.26
@@ -18,6 +17,12 @@ versions:
 - 4.4.12
 - 4.4.11
 - 4.4.10
+- 4.4.9
+- 4.4.8
+- 4.4.6
+- 4.4.5
+- 4.4.4
+- 4.4.3
 - 4.5.0-0.hotfix-2020-08-24-185832
 - 4.5.1
 - 4.5.2
@@ -28,12 +33,12 @@ 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
 - 4.5.16
-
 - 4.5.17
-
 - 4.5.18
diff --git a/channels/fast-4.6.yaml b/channels/fast-4.6.yaml
index 0d374ca5f..7b6eb4ac0 100644
--- a/channels/fast-4.6.yaml
+++ b/channels/fast-4.6.yaml
@@ -19,7 +19,5 @@ versions:
 - 4.5.2
 - 4.5.1
 - 4.5.0-0.hotfix-2020-08-24-185832
-
 - 4.6.1
-
 - 4.6.3
diff --git a/channels/stable-4.4.yaml b/channels/stable-4.4.yaml
index ba33da504..cefd39c95 100644
--- a/channels/stable-4.4.yaml
+++ b/channels/stable-4.4.yaml
@@ -17,6 +17,15 @@ versions:
 - 4.3.18
 - 4.3.13
 - 4.3.12
+- 4.3.10
+- 4.3.9
+- 4.3.8
+- 4.3.5
+- 4.3.3
+- 4.3.2
+- 4.3.1
+- 4.3.0
+- 4.3.0-0.hotfix-2020-09-30-133631
 - 4.4.3
 - 4.4.4
 - 4.4.5
@@ -38,5 +47,4 @@ versions:
 - 4.4.23
 - 4.4.26
 - 4.4.27
-
 - 4.4.29
diff --git a/channels/stable-4.5.yaml b/channels/stable-4.5.yaml
index c726eeda0..7b550a61e 100644
--- a/channels/stable-4.5.yaml
+++ b/channels/stable-4.5.yaml
@@ -1,7 +1,6 @@
 name: stable-4.5
 versions:
 - 4.4.29
-
 - 4.4.27
 - 4.4.26
 - 4.4.23
@@ -17,6 +16,12 @@ versions:
 - 4.4.12
 - 4.4.11
 - 4.4.10
+- 4.4.9
+- 4.4.8
+- 4.4.6
+- 4.4.5
+- 4.4.4
+- 4.4.3
 - 4.5.0-0.hotfix-2020-08-24-185832
 - 4.5.1
 - 4.5.2
@@ -32,7 +37,5 @@ versions:
 - 4.5.14
 - 4.5.15
 - 4.5.16
-
 - 4.5.17
-
 - 4.5.18
diff --git a/hack/backfill.py b/hack/backfill.py
new file mode 100755
index 000000000..49b66d738
--- /dev/null
+++ b/hack/backfill.py
@@ -0,0 +1,44 @@
+#!/usr/bin/env python3
+
+import functools
+import re
+
+import yaml
+
+
+SEMVER = re.compile('^(?P<major>0|[1-9]\d*)\.(?P<minor>0|[1-9]\d*)\.(?P<patch>0|[1-9]\d*)(?:-(?P<prerelease>(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+(?P<buildmetadata>[0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$')
+
+
+def version_key(v, minor):
+    match = SEMVER.match(v)
+    groups = match.groupdict()
+    v_minor = int(groups['minor'])
+    v_patch = int(groups['patch'])
+    if v_minor != minor:
+        v_patch = -v_patch
+    return (int(groups['major']), v_minor, v_patch, v)
+
+
+data = {}
+minors = [3, 4, 5, 6]
+weights = ['candidate', 'fast', 'stable']
+for minor in minors:
+    data[minor] = {}
+    for weight in weights:
+        with open('channels/{}-4.{}.yaml'.format(weight, minor)) as f:
+            data[minor][weight] = yaml.safe_load(f)
+
+for minor, next_minor in zip(minors, minors[1:]):
+    for weight in weights:
+        versions = set(data[minor][weight]['versions'])
+        versions.update(v for v in data[next_minor][weight]['versions'] if v.startswith('4.{}.'.format(minor)))
+        data[minor][weight]['versions'] = sorted(versions, key=functools.partial(version_key, minor=minor))
+
+        versions = set(data[next_minor][weight]['versions'])
+        versions.update(v for v in data[minor][weight]['versions'] if v.startswith('4.{}.'.format(minor)))
+        data[next_minor][weight]['versions'] = sorted(versions, key=functools.partial(version_key, minor=next_minor))
+
+for minor in minors:
+    for weight in weights:
+        with open('channels/{}-4.{}.yaml'.format(weight, minor), 'w') as f:
+            yaml.safe_dump(data[minor][weight], f, default_flow_style=False)