Same issue here. My return was rejected by Fed, but can't uncheck box A in part II, and can't delete the form. No penalty owned, but can't get rid of these issues. Resubmitted, but saw that form 2210 was still included, also with box A checked still, so it will get rejected again. Very frustrating. Online, Self-Employed version.
Update: I tried the suggestion of removing the 2017 tax liability from the questions in the penalty section in "other tax situations", and was able to delete form 2210 after that! I checked to make sure the form wasn't included in what I submitted, and just re-filed. We'll see if it gets accepted.
Next Update: Yes, Fed was accepted!