Okay for the lovers of references. Hopefully the following clears tings up.
Ref AIP.
73.
ALTERNATE AERODROMES
73.1
General
73.1.1 A pilot in command must make provision for flight to an alternate
aerodrome, when required, in accordance with the following paragraphs.
74.
SUITABILITY OF AERODROMES
74.1
General
A pilot in command must plan the flight to comply with the following
conditions for the use of an aerodrome, including an alternate
aerodrome:
Important difference with the phrase "must make provision for", and "must plan for". To my mind make provision for means at any stage during flight, where as plan for is preflight.
Redjet
just give me a reference to the relevant Australian air regulation where it is stipulated as incumbent on me as a pilot to obtain an updated Weather Forecast after dispatch, if such a forecast gets issued during the validity period of the one I already obtained as part of my preflight briefing.
This was never the question, it was once you have obtained said forecast what do you have to do.
From the sound of this you're suggesting that a more recently obtained TAF can be disregarded if the preflight TAF tells you what you want to know??