For a package, if you make the change prior to your 45 day mark, there won't be a change fee; but if you do it after that time, I believe it's a $50 charge. For room only, you have until 5 or 6 days prior to arrival to cancel without penalty, so I assume it's the same for making changes (although I'm not 100% sure on that). As long as it's not the lead guest, you won't have any trouble .
You can remove any guest except the lead guest (the one whose name it's in) from the reservation. Many times a CM will waive the change fee on a package, but it is formally applicable within the 45 day mark. Since removing a guest doesn't change the price of a room-only reservation (unless it was a 3rd or 4th adult), there's no fee for a change on a room-only.
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