>>14106506It depends. IMO, for HoloMyth it was ~3 months, but that's also confounded by the fact they were a new branch.
For Council, they squandered theirs with weak scheduling early which lost a lot of potential tourists rather quickly (NijiEN wave 3 also had this issue, with pretty shit early schedules probably causing a loss of interest even FASTER)
Its hard to guess, especially since the JP side also has their holiday stuff ongoing that may prolong the debut buff a bit.
IMO, February, once the collab ban has ended. Until then, they'll probably slowly drop down in numbers until they stabilize.