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[ShedSimas]

Hi, I'm using SuperCPT to build a plugin. Everything works well in terms of creating the post types, taxonomies and meta boxes. I already had a couple of posts with the custom post types from before I started using SuperCPT, and those work well as well. But now when I try to make a new post in one of the custom types, my meta boxes are riddled with a debug error:

They all have the same error, although the line of reference seems to vary. If I ignore the errors and try to publish the new post, I get this:

Since the error messages aren't pointing to any of my own files, I have no idea what's wrong or how to fix it. (My knowledge of PHP is limited to what I've needed to use.)

It's probably important to note that, now that I've started getting these errors when trying to create new posts with my custom types, they are also popping up in the edit screens for my existing posts, although which fields get the error varies, and the posts seem to save without trouble.

Any ideas?