SQ Transit pax effect on apparent LF
With the SQ SIN-MAN-IAH you have to allow for the passengers in transit through MAN who will not be counted in the MAN-SIN and MAN-IAH figures.
We won't know how many actually are in transit on a particular flight but it seems reasonable to assume that they will account for 25-50% of the total. So if a MAN-SIN has 'only' 120 pax there may well be another 120 routing IAH-SIN transiting MAN, making a pretty full aircraft. The whole 264 seats will not be available for MAN O/D pax and so load factors ex-MAN are more difficult to quantify.
Incidentally I have seen a report showing the Jan 17th switch to A350, quoting 253 seats against 264 for B77W, which is a drop of just 11 seats per flight. With lower operating costs and similar revenues that should be a boost to the bottom line for this route.