Around 2022 to 2023, If you look behind the Boards in the Info hut in City. There will be text that will say "PL CE I  F RES" and behind another one it said "P ACE  N C VE."

It was never solved but originally it was notes for Lemming himself where to put it.
But a few months ago there was different text around the map and there was a yellow crack in the ground That will make a weird noise.

The soundfile was called goodbye.mp3.

But it turns out it was a Jmancurly Update.