Landscape Layers Glitching out

UE4 4.24.3

Having issues with Enable Edit Layers on landscape ticked, getting all kinds of weird issues with tiles flickering out of existence and then the whol landscape going to a million miles high or low and just spazzing out in general. If I turn off layers it doesn’t happen. Going in and out of the landscape tool seems to reset it for a time, but this is just mental. Anyone else seen this?