The airport Kiosk check in machines are now charging the $25 fee to select an offered earlier flight. I thought the $25 confirmed flight change only applied to calling in.

This does not make sense - the kiosk is to provide similar services as a gate agent. You are already at the airport and standby at the airport has no fee. When there are empty seats a standby clears immediately.

So - when an earlier flight is offered, just decline, then simply go to the gate to get on the flight for no fee. Seems like a waste of gate agent time - when the kiosk should do that without a fee.