Hi Unionguy,
I don't work in Sdf, but I can tell like any airline shifts vary though most of sups start off working next day air Mon-Fri nights these are the easiest shifts to handle, mostly 2-4 hour turns. there is also a pretty big weekend operation mostly PS checks(glorified dailys) and other scheduled work, most of those guys work 4 tens days & nights. I am not sure how things are at United but UPS is a very profitable company though raises & 401k matches have been frozen for this year. Ups Sups never talk about compensation so I can't help you there, but I can tell you that we have had alot of sups come from Delta within the last couple of years.
Good Luck on your interview