Faheel,
Australian regulations have never required, in general, always carrying an alternate. It is not particular to Qantas.
Likewise, FAA have a set of conditions where carrying an alternate is not required.
Good advice on Manila to keep very close track of radar vectors and ATC "clearances", there is more than one aircraft sticking out of a mountainside in the area, including a PamAm aeroplane years ago.
Tootle pip!!