Yeah...has happened to me twice but made it.
I am staring to learn to look at gate assignments when just traveling with a carry on. I take the parking shuttle and can just as easily get off at Terminal A.
There is now WN and Alaska using gates in A but based in B...New carrier California Pacific uses B but based in A...quite a chit show. Hoping once they get the new Terminal B Gates completed everyone shifts back to their proper terminals.