Yes, I also can't remove content from collections anymore either. I've just messaged you. Thanks!

Yes. All of the availability dates in my list of products are in the past.

Nope, that only fixed the first error. The "an error occurred submitting this collection, please try again" when I try to add content to collections continues so I can't add content to any collections at all. I'll create a new thread for this error.

OK, I was able to fix my issues. I republished all of the layouts and this resolved the issue.

I am getting the same [BadRequestException] error message on about 1 in 3 collections I try to edit today. Some were migrated, some were created in the new dashboard. I deleted the collections that I couldn't edit and tried to remake them, but I also get the error message when I try to create a new ...