Upgrade Y->J using SWU for AA 107 (LHR-JFK) on Sunday June 2nd: it cleared automatically around 4 hours before take-off.
I could see 8 biz seats available/not assigned on Expertflyer the day before, and it was showing as 'J4'.
So far in 2019: 4/4 SWU on TATL flights cleared.
('low' EXP with ~14k$ spent in 2018 if I recall)