There are 4 seats on the flight deck – all comfortable + the flight deck crew rest area bunks. I do not believe that BA fly with more than 4 operating flight deck crew on any sector, even for check rides. It seems strange that seat 60B remains blocked and even stranger if it flies empty, when a revenue paseenger could use it. I know pilots work hard, I know pilots need rest and I know pilots body clocks can get messed up. However, I still cant see the rationale for a “Captains seat” being blocked especially when there are creature comforts on the flight deck and especially when the Captain rarely if ever, uses it. I am sure one of you clever people can work out the lost revenue on the longer long haul sectors. It would certainly cover the cost of 1 extra cabin crew member.