Indeed "YJ" was delivered yesterday afternoon in EXT for pre-entry mods. ON the 10th the aircraft flies to MAN. (propably to show it off to the head office.
)
On the 11th it heads to Cambridge for training and later that day it arrives at LCY at 1245z to go back to Cambriddge at 1315z.
What happens on the 13th is unknown. On the 14th it operates it's first commercial sectors, starting in EDI on the BA8703, 8712,8717 nightstopping in LCY.
So basically the standard 3 day pre entry mods done in EXT and then straight into promotion/training and entry into service. Not much time wasted to be honest. Maybe one day to cope with unexpeced delays (weather) or something.