This was ever the way on BACF, which the schedule reflected; the demand was different on different weekdays. A lot of travelling consultants went out Sunday evening, spent Monday to Thursday with the client, returned Thursday evening (peak fares), and did Friday in their home office. Well known that MPs do the same (there were always a couple from Scotland/N Ireland in the departure lounge on Thursday evenings). There were other combinations. Business day returns were less usual on Fridays than on other days. The departure peak in the evening was a couple of hours earlier (people worked until 5.30, and got home at 9pm. But not on Fridays). Etc. BACF knew their market very well and have always been better than some others at differential scheduling on different weekdays.