https://ballparkdigest.com/2020/11/02/details-of-mlb-takeover-of-milb-emerge/Reports Sugar Land (probably the Astros) and St. Paul (Twins) added to AAA from the Independent ranks, and Jacksonville (Marlins) would move up from AA. Fresno would drop to Low A (to the California League, which would drop from High A to Low A), with San Antonio and Wichita dropping to AA (Texas League).
I'd assume the Rangers would go back to Round Rock, so this basically leaves Nashville and Rochester as the two open AAA spots, with the Nationals and Brewers the two teams needing new homes. I'm guessing Rochester for the Nationals.
