Originally Posted by
LHR/MEL/Europe FF
Either wait for the A380 the next day, or, if there is a difference in fare (don't think there is on QF like SQ), refund the one you paid for the A380 and buy a cheaper one on the B747.
QF does sell R fares on the 380, so if there is a fare difference between R and F I would expect a refund of the difference
Dave