ChoiceAir Book Now - Pay Later

[Old Coastie]

We are taking the Journey, Aug 27 cruise (Southampton to Lisbon) and have been thinking about booking flights through ChoiceAir.  I noticed today that they are indicating on their reservation site that you can Book Now - Pay Later but I am unable to find any additional details about this feature.  Has anyone used this or have any information regarding this feature.  It states that flights that have the Green Star have this feature.  The only think that I can find for those flights is the ability to cancel (for a fee).

[hiccups]

The thing that would concern me is that if you haven't paid, I'm not sure if Choice Air can book the tickets, and without tickets, you can't select your seat.  I'd get clarification on that before using this option.