BOAC73, all Manchester tours except the 'short tours' (20 minutes for kids) include a flight deck visit. There will be a guide in the P2 seat, the P1 seat and jump seat being available for visitors. We take a max of 4 at a time into flight deck; 2 seated, 2 standing.
On our Technical and VIP tours (where there's ample flight deck time) everyone gets a chance to sit in the P1 seat. On the cheaper and shorter 'classic' tours, there usually isn't time for seat-swapping, but everyone gets to visit the flight deck.