Downgrading 8.5.7 -> 8.5.2

I have done this before with other versions, but I seem to be having issues downgrading my site from 8.5.7 to 8.5.2. I have the folder in the updates directory and changed the update.php file, and when I refresh the site, all manner of errors occur, appearing in the debug console. I even tried removing the doctrine and generated overrides folders with no effect. Thanks.

The database schema from 8.5.2 to 8.5.2 will have changed. So to downgrade you will either need to restore the 8.5.2 site from a backup or identify all the schema changes and reverse them manually.

Maybe you got away with similar before because there were no schema changes between versions.