User blog comment:MisterWoodhouse/The first migrations to the Unified Community Platform/@comment-45645261-20201123113852/@comment-1807002-20201123165138

No, updates will not be done. But migrations (aka phase 1) should be (they recently stated it is still on schedule at about a month+). I suspect most or all of 2021 will be phase 2, much like 2020 was mostly phase 1. And even then I don't see updates to UCP stopping, they just may say a said phase is complete.