Current projections for FAA to allow Boeing to resume 787 deliveries is the "second half of 2022", with some reports suggesting 3rd quarter of the year. After it receives approval I guess it then depends on what position in the line BA are and also how quickly it can (and wishes to) reactivate the fully built and stored 787-10s. My hunch is that combined with the staff shortages and a pared back Summer 22 programme, it will probably be early 2023 as a minimum before we see them starting to filter through beyond the current 2 already in the fleet. I don't suspect BA are in the biggest rush to bring back airplanes into their fleet in the immediate short/medium term whilst they don't have sufficient staff to appropriately manage them within the operation.