I believe explanation 2, actually. I have submitted more than 6 times after the claimed phase-2 start time until now. And I also have a submission that is completed but tagged wrongly with evaluating. And sometimes I get:
You have exceeded the allowed number of parallel submissions. Please wait until your other submission(s) are graded.
Just like Parallel Submission Limit Reached and Issue with Submission.
I also tried to send emails to help@aicrowd.com and crag-kddcup-2024@meta.com but got no responses. For some reason, there seems no official staff cares about this competition. That’s really funny.