As we all know, in Codeforces Global Round 29 (Div. 1 + Div. 2) there were so many submissions solved G abnormally. most of such submissions were deleted from the Final standings, caused significant change for a large of participants' rank.
But participants' rating didn't change with new rank, someone with abnormal submission keeps their high elo up to now. Would this problem be solved? With more contests coming, rollback users' rating would be more troublesome.
Ratings are recomputed in bulk for several rounds together, as is the codeforces norm. You can expect it in any time between now and (roughly) 2 months from now.
Oh, I didn't notice this norm until right now. Thanks for telling me.