I personally would not bother going to BP just to gt 100 or so Virgin miles!
If BP had any brains they'd offering TEN points per $ for a while to get the loyalty rusted on, as Coles and Woolies murder them right now and Virgin is their only hope.
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I think it is 10,000 points to upgrade a short flight off cheapest fare bucket that costs many $100s more to buy.
So on a SYD-ADL 10K I'd do, if seats were there.
Valuing them at 1c a point as I do that means the upgrade "cost" me $100 and that seems about right.