Wiggy, just out of curiosity how do you know whether the weather is within limits? Do the flight crew rely on accurate information from ATC before making the approach or does the weather radar on board tell you what you need?
Also, if you can bear a further question, what happens when a long-haul BA jet ends up at the wrong destination the other side of the world? Does this not cause big problems with duty hours because presumably the crew can't go on to Sydney without rest and there's no stand-by crew as at LHR? Does the captain have to sort this all out?!