Yeah, after testing it some more its even getting stranger. Using something a random name, the filter doesn’t take effect so all is good. When i capitalize one of the cpt name letters that’s when it get crazy. I tried pRojket, projekT, PROJKET and all result in the screenshot above.
Just thought I would add my comments for the next person who comes looking for this information.
My experience just now has been the opposite. From the advice of this thread, I capitalized the first letter of my CPT and that resulted in the screenshots above with sections NOT working correctly.
I reverted back to all lowercase in the PHP and it appears to be working correctly.