Unusual issue - first time for me. I'm flying this evening on a reward ticket (classic reward pts) YYZ-LAX-SAN with the first flight on AC and second flight UA. I've been trying since last evening to OLCI with an Eupgrade to J. I get all the way to the payment then get an error that the request cannot be completed and I have to make the request at the airport. I also tried on the Eup page with the same result. Just got off the phone with AC, who tells me that an OLCI Eup cannot be done because a) I'm flying on a reward ticket and b) connecting to a United flight. They tell me I can try to Eup only at the airport.

This makes no sense to me, particularly given that I get all the way through payment (pts+cash for an Eup from reward ticket) before the request shows an error. Is this the way it is? Seems odd to be, since reward tickets can Eup at T-24 hrs. Thanks.