Very similar to the recent issues [1], [2], [3], [4]. Not sure about i686, as Arch Linux 32 seems to be lagging behind regular Arch Linux currently.

steps to reproduce:
1) open https://www.parabola.nu/packages/?sort=-last_update&arch=x86_64&q=&maintainer=&flagged=
2) compare with https://archlinux.org/packages/?sort=-last_update
3) Remove all servers except the following from /etc/pacman.d/mirrorlist to keep only the main repo and exclude all the mirrors
Server = https://repo.parabola.nu/$repo/os/$arch
4) # pacman -Syy
5) pacman -Ss '^(perl|ugrep)$'

expected result:
Step 2: maximum 1 day lag between Parabola repos and upstream repos, all upstream updates except blacklisted ones are available in Parabola
Step 5: core/perl 5.38.1-1 (or newer) and extra/ugrep 4.3.4-1 (or newer) is in the output since it was updated upstream on 2023-10-13

actual result:
Step 2: it looks like Parabola repos stopped syncing correctly after 2023-11-26, because no updated packages are visible since then, while upstream has dozens (hundreds?) at the same time.
Step 5: core/perl 5.38.0-1 and extra/ugrep 4.3.3-1 are in the output

note:
It looks like armv7h has the same issue.

[1] https://labs.parabola.nu/issues/3374
[2] https://labs.parabola.nu/issues/3436
[3] https://labs.parabola.nu/issues/3497
[4] https://labs.parabola.nu/issues/3542