Is different day flight change possible?
 

I am currently status ExP in AA. I have a trip CUN-MIA-SJU ticketed O in May.

The 2nd leg is one day after I arrive MIA. I wonder if I can fly out as soon as there is vacant on the MIA-SJU route. I understand SDFC has to be "Same Day" but I still want to know any possibility.

Thanks in advance.

No that would involve a change fee and a reissue. You might, and I stress the word might, get a GA to allow you to go standby if the flight (which I assume you are talking the night before) is wide open. But I wouldn't count on it.

1. No as SDFC
2. Possible as standby depending on agent, and available seats
I assume you would not be checking luggage as that would be a problem
3. Pay change fee and fare difference

^ Got it. I think I will try the second advice.

thought checked luggage wasn't a problem if ExPlt.

Unless I'm missing something, since the OP is flying from an international location without pre-clearance, he or she will have to pick up checked luggage at MIA anyway. I would suggest asking the agent at the baggage recheck desk or taking your bags to the general check-in desk and asking there. I have had luck with this before (had a LIR-MIA-LAX(overnight)-SFO ticket and upon arrival was able to get the check-in agent to put me on MIA-SFO direct).