Generally the important premium pax do not like day flights to or from Africa but Economy passengers are grateful for anything! This is proved with BAs operating a day flight northbound from CPT to London for two seasons, but last season this changed to a second night flight with a full day on the ground in CPT. Immediately the revenue increased with many more premiums and less discounting. With daylight flights either way the connections are severely reduced. The long turnarounds are often used for planned maintenance checks. In BAs case these can be somewhat cheaper at out stations than at home base. The BA facilities at LHR are then sold to other carriers who have their planned maintenance checks by BA. Wheels within wheels!