So what should I be doing now to avoid this problem in October?

DH and I have an award booked with AA/BA (with AA miles) in first. Outbound-- Sept 6-- JAX-ORD-LHR-VCE the itinerary shows "print itinerary and receipt. Return--also booked with AA miles--Oct. 9--BCN-LHR-MIA-JAX shows "print itinerary". I brought this to AA's attention once and they said that they emailed me the receipt and that is sufficient.

From what I am reading here, that will not be sufficient on the return trip, especially since we are starting in BCN on BA and won't be on AA metal until MIA-JAX. I am thinking that we will be stuck in BCN with the same problem that I am reading here.

Can I demand that the reservation be fixed now? As I said, I asked once and was told not to worry.
Thanks in advance for your advice.