Update: it looks like new events are now updated; reputation events from earlier this UTC afternoon are still missing:
As of right now, I am starting to get all the notifications that weren't notified before, one by one... perhaps this suggests that this bug is now in the verge of getting fixed (again?).
The total rep is still off, but I'm starting to get more and more notifications now:
Update: New rep changes I get are notified immediately now (like the ones from this answer). Also, my total rep is now up-to-date; my TWP rep on the achievements bar now matches the rep I made today (202):