Okay, this question is WAY premature, but it is also for a friend who is cruising this fall, not just me.

When you're onboard and have the chance to book your next cruise at a discount, does anybody know what the discount typically is, or does it change at different times?

I'm assuming you have to put a deposit down with your new booking... is it the same amount as what you put down when you book in advance from home?

Do they "hold" any rooms for folks who re-book onboard for a cruise that is not that far away? (i.e. you cruise in October, and decide to re-book for the following summer or fall... only 8-10 months away, when the ships tend to be more full and thus more expensive, less rooms to choose from...)

Thanks guys!