Just an observation here, but I flew from Prestwick at the weekend there. The internals of the terminal seemed in pretty reasonable nick. However that may have been like trying to fix a decapitation with a couple of elastoplasts as externally, it looked pretty grim.
It's going to be interesting to see what Romaine Py comes up with, but unless there's some serious investment, I think the terminal's future could be shaky at best.