diff --git a/.github/workflows/build-containers.yml b/.github/workflows/build-containers.yml
index 7809dfe2..7e08a019 100644
--- a/.github/workflows/build-containers.yml
+++ b/.github/workflows/build-containers.yml
@@ -30,7 +30,7 @@ jobs:
 
       - id: image-list
         run: |
-          ORG_DIR=opensciencegrid
+          ORG_DIR_REGEX="^(opensciencegrid|osg-htc)/"
           # Get the list of files changed based on the type of event
           # kicking off the GHA:
           # 1. For the main branch, diff the previous state of main vs
@@ -54,7 +54,7 @@ jobs:
                images=$(git diff --name-only \
                                  "$BASE" \
                                  "$GITHUB_SHA" |
-                        egrep "^$ORG_DIR/" |
+                        grep -E "$ORG_DIR_REGEX" |
                         cut -d/ -f -2 |
                         sort |
                         uniq |
@@ -64,16 +64,21 @@ jobs:
           else
                # List all image root dirs. Example value:
                # "opensciencegrid/vo-frontend opensciencegrid/ospool-cm"
-               images=$(find $ORG_DIR -mindepth 1 \
-                                      -maxdepth 1 \
-                                      -type d \
-                                      -printf "$ORG_DIR/%P\n")
+               images=$(find . -mindepth 2 \
+                               -maxdepth 2 \
+                               -type d \
+                               -printf "%P\n" |
+                        grep -E "${ORG_DIR_REGEX}")
           fi
 
-            image_json=$(echo -n "${images:-dummy}" | jq -Rcs '.|split("\n") | map(select(. != ""))')
-            echo "$image_json" > image_list.json
-            echo "images=$(echo $images | tr '\n' ' ')" >> $GITHUB_OUTPUT
-            echo "image_list=$image_json" >> $GITHUB_OUTPUT
+          # Ensure that the generated JSON array has a member,
+          # otherwise GHA will throw an error about an empty matrix
+          # vector in subsequent steps
+          image_json=$(echo -n "${images:-dummy}" | jq -Rcs '.|split("\n") | map(select(. != ""))')
+          echo "$image_json" > image_list.json
+          echo "$images"
+          echo "images=$(echo $images | tr '\n' ' ')" >> $GITHUB_OUTPUT
+          echo "image_list=$image_json" >> $GITHUB_OUTPUT
 
       - name: Display image list
         run: cat image_list.json
@@ -86,11 +91,17 @@ jobs:
       - name: Set matrix output
         id: set-matrix
         run: |
-          # Run Python script and capture JSON output
-          matrix_json=$(python scripts/build-job-matrix.py ${{ steps.image-list.outputs.images }} | tail -n +2)
-          # Use jq to extract the 'include' part of the JSON
-          matrix=$(echo "$matrix_json" | jq -c '.include')
-          echo "::set-output name=matrix::$matrix"
+          # Handle empty images var, i.e. no images were changed
+          # N.B. an empty GHA output var results in a space, so look for non-space characters instead of just length
+          IMAGES="${{ steps.image-list.outputs.images }}"
+          if [[ $IMAGES =~ [^[:space:]] ]]; then
+            matrix_json=$(python scripts/build-job-matrix.py ${{ steps.image-list.outputs.images }})
+            # Use jq to extract the 'include' part of the JSON
+            matrix=$(echo "$matrix_json" | jq -c '.include')
+          else
+            matrix="[]"
+          fi
+          echo "matrix=$matrix" >> $GITHUB_OUTPUT
           
         
       - name: Verify matrix content
@@ -124,7 +135,7 @@ jobs:
           BASE_OS=$(echo $CONFIG | awk -F'-' '{print $1}')
           OSG_SERIES=$(echo $CONFIG | awk -F'-' '{print $2}')
           BASE_REPO=$(echo $CONFIG | awk -F'-' '{print $3}')
-          CONTEXT="opensciencegrid/${{ matrix.name }}"
+          CONTEXT="${{ matrix.name }}"
           echo "BASE_OS=${BASE_OS}" >> $GITHUB_ENV
           echo "OSG_SERIES=${OSG_SERIES}" >> $GITHUB_ENV
           echo "BASE_REPO=${BASE_REPO}" >> $GITHUB_ENV
@@ -176,7 +187,7 @@ jobs:
           BASE_OS=$(echo $CONFIG | awk -F'-' '{print $1}')
           OSG_SERIES=$(echo $CONFIG | awk -F'-' '{print $2}')
           BASE_REPO=$(echo $CONFIG | awk -F'-' '{print $3}')
-          CONTEXT="opensciencegrid/${{ matrix.name }}"
+          CONTEXT="${{ matrix.name }}"
           echo "BASE_OS=${BASE_OS}" >> $GITHUB_ENV
           echo "OSG_SERIES=${OSG_SERIES}" >> $GITHUB_ENV
           echo "BASE_REPO=${BASE_REPO}" >> $GITHUB_ENV
diff --git a/scripts/build-job-matrix.py b/scripts/build-job-matrix.py
index a8b86388..e255c14e 100644
--- a/scripts/build-job-matrix.py
+++ b/scripts/build-job-matrix.py
@@ -22,8 +22,6 @@ def load_config(config_path, default_config=None):
 
 
 def main(image_dirs):
-    print("Image directories:", image_dirs)
-
     default_config = load_config(DEFAULT_CONFIG_PATH)
 
     include_list = []
@@ -35,8 +33,6 @@ def main(image_dirs):
 
         config = load_config(build_config_path, default_config)
 
-        image_name = os.path.basename(image_dir)
-
         base_os_list = config['base_os']
         osg_series_list = config['osg_series']
         base_repo_list = config['base_repo']
@@ -56,7 +52,7 @@ def main(image_dirs):
         # 1. Simplicity: Using a single string to represent configurations is straightforward and easy to understand.
         # 2. Integration: A single string is easily passed to external tools and systems that manage builds.
             configuration_string = f"{base_os}-{osg_series}-{base_repo}-{config['standard_build']}-{config['repo_build']}"
-            include_list.append({"name": image_name, "config": configuration_string})
+            include_list.append({"name": image_dir, "config": configuration_string})
 
     sys.stdout.flush()
     json_output = json.dumps({"include": include_list}, indent=4)