It happens in replies and comments as well, not replying or tagging in to something until the flip over, as if saving up ideas and tags for the next month, or just because they assume everyone else will be doing likewise.

AC will always affect activity towards the end of the month, but most other games I've been in, (and for many people in this game as well) that tends to result in the "end of month scramble" as people go "wait no, crap, I thought I had more!!!" and desperately flail around to get a few more tags in to meet their goals. The contrary pattern of people just... stopping being part of the game for a while seems to run counter to how AC is (in theory) supposed to work.

If an easier way to link sub threads would make people continue to tag as normal, maybe that should get looked into?