Thanks, I was wondering about that but too lazy to look it up. My first thought was the possibility of mixing/matching crews/planes on routes by later this year - US would take over a BOS-ZRH route with a 767 while AA crews/planes might add capacity to a PHL-Europe route. But with your info it seems that the res system hiccuped with the codeshares - BOS-ZRH operated by AA crews/planes but also carrying US flight numbers.

Jim