I have had to change the flight of a particular segment on my xONE. It is the same day just different flight number.

The ticket is AA issued ex CAI but the flight change is for a CX sector.

I rang AA and they have modified the booking on their systems.

Is it preferable for me to go to AA desk or CX desk at LHR to get the paper ticket sorted?
Do either charge an admin fee for this service at LHR?

I know the CX 5 digit code so that won't be an issue when speaking to them.


Thanks
Moomba