Pretty widespread J award availability on AA 155/156 (SEA-LHR-SEA) this fall and winter. I would assume this route is a dumpster fire for AA considering COVID + offfseason, so I would grab it while it's hot (read: I expect AA will cancel this route eventually- I don't think their putative SEA longhaul hub is going to work well against DL). The availability pretty much disappears after early April.
(Anything that is 57.5k + $38 is AA J.)