I've been noticing $subject for a while. For example, navigating to
today's messages for pgsql-hackers@ [0] intermittently shows me nothing for
long stretches of time. My suspicion is that this has something to do with
the increased cache time patch committed back in March [1].
[0] https://www.postgresql.org/list/pgsql-hackers/since/202609020000/
[1] https://git.postgresql.org/gitweb/?p=pgarchives.git;a=commitdiff;h=c151a8
--
nathan