Originally Posted by
jsloan
The clock would reset with a cancel and rebook, but not with a change.
Since we're talking about an award reservation, I believe it would only reset if you redeposited the miles. Otherwise you still have a ticket and a PNR, and thus only the single 24 hour window to change/cancel.
But the more important issue here is that the strategy likely won't work because you typically can't hold the outbound partner flight through a ticket reissuance.