Open Mainframe COBOL course - worth the time?

Coming from a bootcamp background. Saw the Open Mainframe Project COBOL course mentioned in a few places. Is it enough to be useful on a real job or just a taste?

Applying for junior mainframe roles and trying to prioritize what to learn first.

Did the labs last year. Good for syntax and z/OS navigation. You still need JCL and something online like CICS or DB2 to sound credible in interviews.

Better than youtube randomness. Not a substitute for a mentor on your first compile proc.

Started it. The z/OS lab access alone was worth signing up.