Not quite. if you have 10-19, there will only be 7 groups in finals. If there are 20-29, 10 groups in finals. Over 30 in prelims, there will be 12 in finals. Less than 9, you only have prelims to select those that advance to State.
It doesn't matter how many actually perform at Area. The number advancing is purely off of those bands that receive a 1st division at the Region level.
8 groups from Region 18 advanced to Area. This means that all 7 groups in Region 26 need a 1st division to advance 6 to State. I'll keep everyone updated.