5.5 Assertion failed: (Index >= 0) & (Index < ArrayNum) when loading Skeletal Meshes

I’m getting this assert followed by a crash with UE5.5. This only happens for skeletal meshes that work in 5.3 with no issue. I can remove them (not really a solution) but is this a known issue that can be fixed without me having to rework a bunch of skeletal meshes?