Originally Posted by
zrs70
Think the late December changes have already gone through.
That's said... I would hold onto the ticket right up until flight time. If there is a change or delay, you will have leverage. For now, purchase a separate ticket for your trip.
If the OP really wants one F ticket instead of 4 Y tickets, an agent won't do that, no matter how big a schedule change. Whether one wants to use a strategy to hold on to all the tickets in case of IRROPS, is up to them. But there's no need to rebook (unless they want to pay outright for the F ticket). They can still cancel 3 of the tickets and keep one. Either way, a split will be necessary, so no reason not to do that now to make it easier when cancelations are done.
On the other hand, if any of the other three want to use the funds on the existing PNR for another trip booked before this one starts, that would be a reason to cancel first. Travel on the existing PNR must be completed within one year of the original date of issue, so in case they don't travel much, this could be a factor.