Strange ragdoll issue

Hi, recently I noticed that when I’m on PHAT if I set physics blend between 0 and 1 (so basically any value ) I can’t interact with some parts of the mesh like the legs. I noticed this while using 4.13 and SK_Mannequin with default physics asset but I also have 4.14 and 4.15 and this weird behaviour is still there. Is this part of a new feature?

Posting comments on your other report to clarify if these are separate issues.