The rumor is there will be four High-A Leagues, including the Carolina League, with many teams switching classification between High and Low A: https://ballparkdigest.com/2020/11/07/let-the-affiliate-dance-begin/ Northwest League at six teams mentioned here: https://ballparkdigest.com/2020/11/02/details-of-mlb-takeover-of-milb-emerge/ Mid-Atlantic League at six teams mentioned here: https://www.baseballamerica.com/stories/binghamton-brooklyn-survive-as-mets-announce-2021-minor-league-affiliates/ The Midwest League at twelve teams is mentioned here:
That leaves six for the Carolina League, so that was my logic there. The first link I shared also mentions the South Atlantic League would be twelve teams. I also removed the teams in that region that were on the original hit list (Frederick, Hagerstown, Lexington, West Virginia Power) to get the teams to this breakdown, and moved two others to the new Mid-Atlantic League. Here's my guess at the Mid-Atlantic League, fwiw, though no real idea on the sixth team, so I just put Trenton there for now. Could be Lowell, like that other article said. Could be Tri-City or West Virginia Black Bears, not on the original hit list: Aberdeen – Orioles Brooklyn – Mets Hudson Valley – Yankees Jersey Shore – Phillies Trenton – Rays Wilmington – Nationals