Different room types on the same reservation
 

How do I book, using the website or the app, a reservation with two different rooms (e.g., one with a king size bed, one with two queen beds)?

Book 2 rooms with same bedding, then go back and change one of the two to the other bedding option. It will look like it's all attached but it really has two separate reservation numbers

There's a small risk that the rate may change in those few minutes...

Clever!

Unfortunately it doesn't seem to work. When I try to modify one of the rooms, I get all the way to picking the new type of room, I click on what I want, and "we encountered a system error". I tried later again, same deal. I'll try a few more times before I call, though.

I've done this tons of times, last was in May this year...

Whenever I've been hit with 2max occupancy for our family of 3 adults, I book 2 rooms under one booking, leaving the first as one king for two and change the second to two doubles for two

I usually just make 2 separate reservations.

When the hotel somehow upgrade one of the room, they will split the reservations into two separate reservations anyway.

+1. I have also made separate reservations for this scenario (2 or 3 rooms with a mix of different room types).

--Jon

Curious what benefits are there for having 2 different room types under one reservation, versus simply making 2 separate reservations?

None as far as I know, as it makes a separate reservation for every room.

the "master" reservation number just brings up all the rooms, while the others only bring up one room

After editing, each can be different room types, and the arrival/departure dates don't even have to match...

Different check in/out date will make the 2nd reservation ineligible for Bonvoy points

Correct now

But it was fine in "the old daya"