I booked my EWR-LHR tixs in January.

THe agent told me this is one of the busiest routes for miles for upgrades, so I ended up getting waitlisted.

My return cleared about 3 weeks before flight.

My departure cleared about 30 secs after I arrived at the RCC Desk. The Angels at the EWR RCC said the upgrade came thru literally as I asked for it. That's funny.

SO I would book and about every week before departure check on the upgrade status. DON'T FORGET TO ASK at check-in if you still haven't cleared!