Additionally, EWR-LIM departs mid-afternoon, so it would be quite difficult for the "late" LHR-EWR aircraft to continue on to LIM. The earliest flight from LHR might work, but alas, that's the 772...

This being said, I did have the flat beds on EWR-LIM in mid-April. Unfortunately, we didn't have them on the redeye back, though for whatever reason I slept quite well in the old recliners...