I have relies on 5 acres near cnr Henley st/Lord st. I don't think flight path has changed. I never noticed planes until 3yrs ago when kids were doing horse riding lessons for an hour. I don't think it was too noisy though. My friend at Guildford with planes and trains and a 450sqm block, I didn't find appealing!
My research has found that in Winter due to prevailing winds that planes will approach from the south and use runway 3. In summer and at any time the winds are favourable they will use approach from the north (over Swan Valley) and land on 21. Runway 3 and 21 are the same runway but called differently depending on the direction of approach/departure as it is named after their compass bearing.
All planes are to use 21 (approach from Swan Valley) whenever possible to minimise noise on higher density areas.
Departure noise isn't an issue for Swan Valley as they head out to the coast or east quite quickly.