Every $10,000 you add is another Arlo it can run for you. Take money out and it runs fewer.
One seat is taken per call. Each standing seat is a reservation on your balance, and your balance sets the limit. Settled capital does not return to the queue automatically. Enrol it again when you choose. Any delay is optional and off by default. If the account falls under $10,000 it simply stops: nothing is borrowed and nothing overdraws.