Originally Posted by Furby

Yes, one PNR can contain separate tickets although that is not normally the case. Everything you said points to separate tickets specifically the 62.5K miles required, and the need for award seats to be available when rebooking the JTR to LHR flight but not the LHR to JFK flight.

It’s possible that when the flight schedules changed there was insufficient space for all Club Europe tickets and using AA miles for an award ticket probably put you lowest on the totem poll for being downgraded. More likely your new LHR to JFK flight needed a different connecting flight from JTR and the details of the original flights and the new flights are perhaps a bit more than you recall.

Either way, as mentioned previously the difference between CE and Economy on this route is negligible unless you need the extra baggage allowance. You will lose out on an empty middle seat and a light meal. Same leg room and everything else. Bring a snack on board and you will be fine.

However you should get what you paid for. Keep your boarding passes. After you have flown, contact AA, tell them you have boarding passes showing economy travel and (hopefully) proof that 22.5K miles were deducted not the 12.5K that are correct for economy travel and request that 10,000 miles are refunded. Or, if you have proof that you have a ticket issued in business class (which should be in your original receipt) claim EU261 downgrade compensation which will be 75% of the miles and fees paid for that sector. That claim has to be made with BA and it will be complicated because you paid with AA miles and they cannot give you AA miles in compensation. The EU 261 compensation route will be very long and frustrating and quite likely to fail, so I would go with the AA approach and cut your losses.