That's right, and it remains something of a mystery as to why an open 355 day advance booking schedule with F availability has suddenly been curtailed. I wasn't paying much attention to dates, but it seems to have happened sometime in past week: all F sales have been removed for a period of 5 months from late October 2017 thru March 2018. Maybe the same 4 class aircraft will continue to be used but BA are holding off on selling any more F in case they decide to change or upgrade the 772 aircraft sooner than expected?