I booked my trip yesterday.  I didn't notice that they charged for the whole trip.  Last year they charged something like $109 when you booked.  This year for two people and 6 nights it was $160.  Not a lot of difference, but if you had a larger group the difference would be much more.

Also if you haven't been to the site since October 2019 you will need to register again including a new name and password.  The site is somewhat confusing at first, but that happens when you get old.

I know you can add more people later. I tested that out when I made my reservation.

Can you do that? book less days and/or people and expand later?

booked my Q trip yesterday.  found out that they now require full payment for your trip at time you make the reservation.  Didn't have to do that in prior years.

not a big deal, but best to be conservative on number of days and number of people, and adjust when you get there if you need to add more days I think