Migration errors 9.1.2 to 21.6.1: 'Project' object has no attribute 'get_option'

Tried again doing 9.6.1 → 20.11.1, clean volumes, it came up with projects and users, but there’s still no events in the GUI of any of my projects after migration. Any tips for investigating why?

Perhaps will try going to some other versions in the 21.x series.