Originally Posted by
canyonleo
Yes.
But, better to just call your Diamond Line rep (if you are Diamond) and have them "merge" the two so you don't even need to consider that a move mid-reservation is possible.
This is extremely common. Any Hyatt agent can link the reservations together. It's advisable to let the front desk agent know you have the multiple reservations when you check in, but that's primarily for your piece of mind.