Seems like this was the first post-commit failure: https://builds.apache.org/view/A-D/view/Beam/view/PostCommit/job/beam_PostCommit_Python_Verify/7855/
(the one before this also failed but that looks like a flake)
Looking at failed tests I noticed that some of the were due to failed Dataflow jobs. I noticed three issues.
(1) Error in Dataflow jobs "This handler is only capable of dealing with urn:beam:sideinput:materialization:multimap:0.1 materializations but was asked to handle beam:side_input:multimap:v1 for PCollectionView with tag side0-FilterOutSpammers."
(2) BigQuery job failures (possibly this is transient)
(3) Some batch Dataflow jobs timed out and were cancelled (possibly also transient).
(1) is probably due to https://github.com/apache/beam/commit/684f8130284a7c7979773300d04e5473ca0ac8f3