Originally Posted by NM
Its rare for such a change to be an unscheduled substitution. Most times the 743 operates QF25/26 it has been in the schedule for at least a month before due to planned maintenance for the 744 fleet. I would say the risk of getting an unscheduled 743 on that rote is low.
Havign a month's notice may not be any consolation if there is no availability (in discounted business or award business) on the other flights, or unable to move dates due to commitments.