What happened today on production with Assignment Enhancement preview course setting?

Very confused. Midday today there seemed to be new features pushed to production if the course setting to preview assignment enhancements was set to "Enabled" (which seemed to happen by default at so...

API error 400 when submitting assignment

Hi all, our users have recently started receiving this error 400 response from the API when our system submits an assignment. It doesn't happen necessarily to all users, but more and more so recently...