Yeti&Pepe don't respawn at Sharp Cliff 3

Immediately after maintenance, Sharp Cliff 3 map is normally populated with Yeti&Pepe mobs.
However, as they are killed, they do not respawn (or only respawn sometimes), and within a day or two there are none to be found on any channel.

This may or may not be related to Snowman spawning in this map again (after being exiled to a master monster portal, which was taken away recently).

I noticed something similar on the Florina Beach map Hot Sands where King Clang spawns.