Originally Posted by
gusd
But these are not really relevant. I was mainly looking at in principle, as I see 2 possibilities for any itinerary to anywhere in Europe for me at this point:
1. Book now to take advantage of P/PZ - disadvantage: schedule change hacking up the itinerary, having to reroute
2. Wait for the schedule change to get a more stable itinerary, somewhat less likely (though anything can happen) to get schedule changes - disadvantage: P/PZ gone, tickets becoming more expensive for the same itinerary for the same day.
If the currently-published schedule is agreeable, there is absolutely no advantage to waiting. If there's a schedule change, you now have the ability to pick any UA flight that you wish, and keep P/PZ regardless of the current availability, or to get a refund if necessary. If there's no schedule change, then you don't have anything to worry about.
In the vast majority of cases, a schedule change is a good thing for the traveler.