Why occansional gauge (aircraft size) changes?
So I noticed when looking at AUS-LAX there's a flight on 4/29 where the typical E-175/CRJ-700 United Express has been replaced by United Mainline with a 738 (UA305). Anyone know why this would happen? Could this be the start of mainline service on this route or is this just aircraft reshuffling that has affected this one flight?