diff --git a/azure/posix.yml b/azure/posix.yml
index b1e9c69..9c90bdc 100644
--- a/azure/posix.yml
+++ b/azure/posix.yml
@@ -90,7 +90,7 @@ jobs:
 
       - bash: |
           set -e
-          if [ "$BUILD_REASON" == "Schedule" ]; then
+          if [ "$BUILD_COMMIT" == "master" ]; then
             ANACONDA_ORG="scipy-wheels-nightly"
             TOKEN="$MAPPED_NUMPY_NIGHTLY_UPLOAD_TOKEN"
           else
@@ -111,10 +111,12 @@ jobs:
 
       - bash: |
           set -e
-          # The --force option forces a replacement if the remote file already
-          # exists.
+          source extra_functions.sh
+          for f in wheelhouse/*.whl; do rename_wheel $f; done
+
           echo uploading wheelhouse/*.whl
-          anaconda -t $TOKEN upload --force -u $ANACONDA_ORG wheelhouse/*.whl
+
+          anaconda -t $TOKEN upload -u $ANACONDA_ORG wheelhouse/*.whl
           echo "PyPI-style index: https://pypi.anaconda.org/$ANACONDA_ORG/simple"
         displayName: Upload to anaconda.org (only if secret token is retrieved)
         condition: ne(variables['TOKEN'], '')
diff --git a/azure/windows.yml b/azure/windows.yml
index b745a03..14eb6a0 100644
--- a/azure/windows.yml
+++ b/azure/windows.yml
@@ -118,7 +118,7 @@ jobs:
 
       - bash: |
           set -e
-          if [ "$BUILD_REASON" == "Schedule" ]; then
+          if [ "$BUILD_COMMIT" == "master" ]; then
             ANACONDA_ORG="scipy-wheels-nightly"
             TOKEN="$MAPPED_NUMPY_NIGHTLY_UPLOAD_TOKEN"
           else
@@ -139,10 +139,12 @@ jobs:
 
       - bash: |
           set -e
-          # The --force option forces a replacement if the remote file already
-          # exists.
+          source extra_functions.sh
+          for f in numpy/dist/numpy-*.whl; do rename_wheel $f; done
+
           echo uploading numpy/dist/numpy-*.whl
-          anaconda -t $TOKEN upload --force -u $ANACONDA_ORG numpy/dist/numpy-*.whl
+
+          anaconda -t $TOKEN upload -u $ANACONDA_ORG numpy/dist/numpy-*.whl
           echo "PyPI-style index: https://pypi.anaconda.org/$ANACONDA_ORG/simple"
         displayName: Upload to anaconda.org (only if secret token is retrieved)
         condition: ne(variables['TOKEN'], '')
diff --git a/extra_functions.sh b/extra_functions.sh
index 1a58c66..0c5fb63 100644
--- a/extra_functions.sh
+++ b/extra_functions.sh
@@ -29,6 +29,22 @@ function teardown_test_venv {
             source venv/bin/activate
         fi
     fi
-} 
+}
+
+function rename_wheel {
+    # Call with a name like numpy-1.19.0.dev0+58dbafa-cp37-cp37m-linux_x86_64.whl
+
+    # Add a date after the dev0+ and before the hash in yyymmddHHMMSS format
+    # so pip will pick up the newest build. Try a little to make sure
+    # - the first part ends with 'dev0+'
+    # - the second part starts with a lower case alphanumeric then a '-'
+    # if those conditions are not met, the name will be returned as-is
+
+    newname=$(echo "$1" | sed "s/\(.*dev0+\)\([a-z0-9]*-.*\)/\1$(date '+%Y%m%d%H%M%S_')\2/")
+    if [ "$newname" != "$1" ]; then
+        mv $1 $newname
+    fi
+}
+
 # Work around bug in multibuild
 if [ ! -o PIP_CMD ]; then PIP_CMD="$PYTHON_EXE -m pip"; fi