When I apply the subdivision scheme to my render mesh, I notice some uv "smoothing" or stretching at the edges of the uv shells. Is there a way to control this behavior?

It's hard to say without inspecting the mesh, but there was a bug that manifested in a similar manner prior to 19.5.563. If you're on an older build please updating and see if it fixes your issue.

I may not be able to get our facility to upgrade for this. But I did test in mantra and got the same behavior. I think I need to reinforce the edge loops to correct the issue, which does seem to work in my testing.