I attempted to download the fix_upgrade branch from the link, but it does not appear to be there any more. Let me know where I can access it, and I'll report back with my findings. We're currently on 2.4.24, so that would also be my baseline attempt.

[EDIT: I see there are updated scripts now in the master branch, and suspect you've merged all fix_upgrade files into master. Would like to confirm I should use master now instead of fix_upgrade.]