Yes! Balance Priority works with multiple groups and multiple rooms to fill rooms evenly. It doesn't matter how many people check in from each group, if the priority is set to balance evenly, the emphasis will be to fill the rooms one at a time.

Rooms are assigned at each search and are maintained if the participant does not check-in. For example, if our two Rooms are "Apples" and "Grapes," and the last room that was filled is "Apples", the next Room Assigned will be "Grapes". But, if the check-in is canceled or the search expires, the Room Assigned is still "Grapes" until someone completes a check-in.

Check-In Suite balance priority fills rooms by each family's check-in. So it is possible for two (or more) participants in the same household to check into the same room at the same time, even if the room is technically overfilled.

Your balances might also be "off" if the two rooms have different Maximum Capacities. For example, if your Peaches room has a Maximum Capacity of 20 and your Strawberries room has a maximum capacity of 10, Check-In Suite balance priority places the first ten participants into the bigger room (in this example, Peaches) and then rotates between the two rooms until it places 30 participants. It will look like this:

If you want the rooms to fill evenly without consideration for a larger room, set the Maximum Capacities to the same value.