diff --git a/.github/workflows/build_test_publish_images.yaml b/.github/workflows/build_test_publish_images.yaml
index 8965c5e389..b4f92013b5 100644
--- a/.github/workflows/build_test_publish_images.yaml
+++ b/.github/workflows/build_test_publish_images.yaml
@@ -84,7 +84,9 @@ jobs:
       - name: Compute cuopt version
         id: compute-cuopt-ver
         run: |
-          ver=$(rapids-generate-version)
+          source rapids-datetime-string
+          # .post<datetime> makes every nightly version unique (see ci/build_wheel.sh); ignored on release builds.
+          ver=$(RAPIDS_VERSION_SUFFIX=".post${RAPIDS_DATETIME_STRING}" rapids-generate-version)
           # Remove starting 0s from version 25.08.0a18 -> 25.8.0a18
           CUOPT_VER=$(echo "$ver" | sed -E 's/\.0+([0-9])/\.\1/g')
           echo "CUOPT_VER=$CUOPT_VER" >> $GITHUB_OUTPUT
diff --git a/ci/docker/Dockerfile b/ci/docker/Dockerfile
index 33ccd9d3ed..bd63e4337e 100644
--- a/ci/docker/Dockerfile
+++ b/ci/docker/Dockerfile
@@ -33,7 +33,12 @@ RUN apt-get update \
         gnupg2 \
         wget \
         unzip \
-    && add-apt-repository ppa:deadsnakes/ppa \
+    && ( for i in 1 2 3 4 5; do \
+            add-apt-repository -y ppa:deadsnakes/ppa && exit 0; \
+            echo "add-apt-repository failed (attempt ${i}/5), retrying in 5s..."; \
+            sleep 5; \
+         done; \
+         exit 1 ) \
     && apt-get install -y --no-install-recommends \
         python${PYTHON_SHORT_VER} \
         python${PYTHON_SHORT_VER}-dev \