Originally Posted by BoeingBoy

Is it strictly an equipment change only or do the times change also?

If only an equipment change, it's doubtful that they'd let you rebook for that reason alone (although if it is now oversold they might). Chances are better if there's also a schedule change.

Jim

ps added after seeing other replies - I think the concern is that Express flights might be more likely to be canceled in irrops than a mainline flight.