SYD-MEL slight departure time changes

[Melburnian1]

QFd has an 0935 hours (QF431) and a 1010 hours (QF433) SYD to MEL flight.

Was this minor change from the usual clockface '00' and '30' (with '15' and '45' minutes past the hour at peak times) made because there were no slots available given the large number of international departures from Sydney airport midmorning?

 

[Saab34]

I see 0930 has three widebody departures so perhaps shuffled for sequencing.