Standby for flight with different routing?
I am booked on the JFK-SEA nonstop in a few days, but I'd really like to rack up some extra miles. Is it possible to standby for a JFK-LAX-SEA or JFK-DFW-SEA on the same day? Would the check-in kiosk give me such an option, and would both legs be confirmed at the same time?
My guess to these questions is no, but in that case, could I do this by paying the $50 same-day change fee (assuming there is space)?