Today I hit the repcap with 200 rep (in fact I got a few null upvotes after that, so that I 'should' have been on 230 rep). Then somebody undid their upvote on one of my answers1, putting me down to 190 rep. After that, every upvote I got still counted as null: apparently my maximum rep today is 190.
Surely this isn't how the system is meant to work? I know from experience that if someone loses rep after hitting the repcap by being downvoted or by downvoting answers, then the next upvote they get brings back the rep they lost. I can't see why it should work any differently when they lose rep by having upvotes reversed.
Is this behaviour intentional or a bug?
1 (I suspect this unupvote was accidental, since I hadn't made any major edits since posting the answer, except to explain some of the clues better after help from the OP. But that's neither here nor there.)