I updated the source of a package of mine last night. The upstream is on Github, and I use the %forgemeta macro for an easy spec file. When I tried to run "fedpkg build" though, it failed - the build system rejected the build because it was expecting an SRPM with a release string including 20230507, but instead got one with 20230506.
I submitted a bug against redhat-rpm-config; the forge macro code calls "date" with -u (for UTC), so that shouldn't happen. But then I thought: unless somehow there's a clock wrong? Like maybe something thinks the hardware clock is UTC but it accidentally is local time? That seems rather unlikely, but wondered if somebody might could check.
For now, I just explicitly defined the date string to use, and that worked, but it's still weird.