The Partial Blocks MVP release requires a schema change to function correctly.
This change was discussed and approved by TechCom in T199917.
The work around the change is in T197144 while the actual patch is here: https://gerrit.wikimedia.org/r/c/mediawiki/core/+/440871
The core change is the addition of a field `ipb_sitewide` on the `ipblocks` table and the addition of a table `ipblocks_restrictions`.
There is no data migration that needs to happen for this schema change. It is additive only.