This script is related with migration error on upgrade from 8.5.2 or before.
You can check if there're missing migrations on your concrete5 site before upgrade it.
- Download checkMigrations.php and upload it
- Run it with
c5:exec
command
concrete/bin/concrete5 c5:exec checkMigrations.php
Migrated: 165
Not Migrated: 0
All migrations are already run on your concrete5 site. Feel free to upgrade concrete5.
20190309000000
Migrated: 164
Not Migrated: 1
It means 20190309000000
never run on your concrete5 site. You should consider to rerun it before update core.