Upgrade on BA using AA miles
 

Made a mistake and booked LIM-MIA-LHR through BA website, now Im trying to award upgrade but Im stuck because BA doesn't handle AA miles and AA didn't issue the ticket. AA offered complimentary systemwide upgrade but its only for 2, and we are 5.
LIM - MIA is AA1558 / BA4840
MIA - LHR is BA0206
Any suggestions?

If you booked within the last 24 hours, cancel and you can then rebook with AA - BA allows cancellation within 24 hours of booking without penalty on all routes

Otherwise, if the upgrade is important, you need to consider what the cancellation penalty is , what the new fare is and decide whether it is worth it

You can use AA miles to upgrade as long as one segment has an AA flight number on it (since you didn’t book with AA). You don’t specify but I suspect you booked both legs as BA codeshares, but maybe call BA and see if they can switch one leg to be AA marketed?

https://www.aa.com/i18n/aadvantage-p...r-airlines.jsp