This has been found in 1.2.6
This is not what you might think it is, it has to do with the loading zone and how it triggers. To provide background I am using the normal sized forest secret base and I tried lining up a movement tile to launch me out of my secret base. The tile loaded the zone faster than usual and I maintained the sliding from the tile after going back into the Pokémon centre. Which forced me into the wall on the other side of the building.
From some points in the game this could be escaped but at most I am pretty sure this is a soft-lock. For reference I put the tile in my base (CannedPotato). Also I did not know what priority this is, being a way to stop the player from ever continuing that file I labelled this as major but feel free to change it if you can/want.