Originally Posted by
ESpen36
If your luggage is tagged to the final destination, then AA will transport it there eventually. If you have a missed connection at the hub, your luggage will NOT be loaded onto the connecting flight (because 100% positive bag matching is required on international flights). If your luggage is mishandled and delayed, AA will take maintain custody of the luggage through customs clearance as necessary.
I doubt that you would be able to retrieve your luggage at MIA if you misconnect, since the luggage will remain in the bowels of AA's operation. It will be moved to your new flight to BCN (presumably connecting through LHR or MAD, or perhaps the next day's nonstop flight to BCN). Of course, if you change your mind and decide not to travel, AA will release your luggage to you.
Are you sure PPBM will affect it? A connection of mine was messed up by weather going from CUM-MCI-DFW-GRU where I was rerouted at MCI to go the next evening to MIA and then to GRU the next day, and my bag was sent to DFW without me and actually got to GRU without me being on the GRU flight (since I had been rerouted to MIA for he following day)