Rejection of federal return because of F2210-003 part ll line A and I cannot uncheck box. what should I do?

Suggestions: 1) try fix in answer below. 2) : Delay further action until after 1 March. TurboTax is aware of 2210 issues, working on it, 1 March is the updated ETA for fix. See <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/4614351-is-the-form-2210-error-fixed">https://ttlc.intuit.com/questions/4614351-is-the-form-2210-error-fixed</a> for possible fix now.

I have been advised by TT Support that the fix has been postponed until March 1st - very frustrating!

I've been fighting this problem for 3 days, but now solved.  This is what I did.

Go to Forms (icon in the upper right corner in the blue band).  Then choose Form 2210 from the list on the right, and scroll down to Part II.  You cannot un-check Line A, and there is nowhere to enter a [WaiverExplanationStatement].  But on Line B there is a gray box on the right that says "Explain".  Click on that box and you will get a form for an explanation.  Type in "There is no penalty due."  Now return to the Step-by-Step (icon in the upper right corner), re-save your file and re-submit your e-filing.

Even though I was not able to put a check on Line B, my federal e-filing was accepted.
From Rakeyser that also worked for me