Thought I would throw this out here rather than in "Post your cheapest flight", which inspired me to shop.
Seems there are some low fares out there on American for the spring and fall. Just booked Philly-> London, return from Dublin basic economy (which we are satisfied with) for $401, end of August. The price breaks, as in low to mid $400s, included Paris, Berlin, Amsterdam and Edinburgh from here, not so much further into Europe East for South (save for Barcelona). Similar for spring which we had already booked at what we thought was a low price under 450, now 10% lower. AS we are in Philadelphia, I did not grind this through to see how this played out in other American hubs. The prices I was seeing on AA reflected on British Air, sans ability to purchase seats on American. We have never gone the seat purchase route before, but when we could get what we wanted for only $12/seat on top of a low price, why not.