There's this in the rules:
Changes after commencement of travel and up to 24 hours prior to commencement of a subsequent Flight Segment
14.7.8 Subject to this clause 14.7, the following changes are permitted to Qantas Flight Segments and a Change Fee per passenger will apply (see the
Fee Schedule):
(a) change to flight number;
(b) change to date of travel;
(c) change to class of travel; and
(d) change to a direct or indirect Segment routing without a Stopover (provided that the origin city, the destination city, and the airline remain unchanged).
These Terms and Conditions form the basis of Qantas Frequent Flyer, to protect both Members and the Qantas Group.
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