I just tried using 2 PLA layers for support on a PETG project. I just saw the printer when it stopped printing the PETG and loaded the PLA. It printed one dot of PLA on a support tree and then went back to printing the PETG. It is just halfway through a 13-hour print job but I haven’t been watching it and don’t see any more white PLA spots on the camera or direct viewing of the print job.
I am facing the same problem. but this must be a bug, not settings related
you can see my topic with screenshots here:
did you turn on prime tower?
I was running into this same issue, but here’s what fixed it for me!
I had to add the PLA support material as another material in this project. Then I was able to select it as the support material or support interface material.