The QF/BA lounges open just in the afternoon (1500, says the website) - making them unusable for CX 650/710/736/690/712.

GB's point about the location is spot on - the only times that i've been to QF's lounge has been before CX711, given that i dont usually get to Changi too long before my flights, making the 'C' gates location of the QF lounges a tad inconvenient for CX's 'D' gates. (except 711, for which i end up waiting a bit given the small gap after my work-day).

Fairly certain that GB would know CX's sched like the back of his palm (even though he got the B/C/D gates wrong )