Currently on MacOS running configure with --with-source-date=version
results in:
16:46:08 checking what source date to use... unavailable
16:46:08 configure: error: Cannot convert DEFAULT_VERSION_DATE to timestamp
16:46:08 configure exiting with result code 1

I think it's due to recent change https://github.com/openjdk/jdk/pull/7733/files
which does not handle the case where there is no "time" specified any longer, which is what happens using DEFAULT_VERSION_DATE from version-numbers.conf => "2022-09-20"