Every year seems to be a little bit different. Typically, a team that finishes in 1st or 2nd place would move up. They would also need to apply to move up. And then be approved by the technical committee.
This past year- I don’t know of any teams that finished in 1st or 2nd place that weren’t approved.
Lower placed teams can also apply and if they added a bunch of strong players and had a dominant spring and summer tournament showing, they would be considered to move up.