Can thsi be doen? Can I book a trip and borrow the extra few poinst from the following use year at the same time? Or do I ahve to borrow beforehand so that thsoe poinst are in the system to book the trip?
That is the way that it is done. You can't borrow points unless it is to book a trip. Once borrowed, they stay in that Use Year even if you cancel the trip later on. I don't think you could borrow points if they weren't attached to a trip.