It seems I've made this mistake as well, and forgot to add my 1095-A information when I originally submitted my federal return, which was accepted. I received a letter LTR 12C saying I need to submit an 8962 and 1095-A, and not to amend / respond with 1040X.
I used the search tool and there were several answers spanning several years (2016, 2018, etc) most of which suggest "adding a state" (but not really) but the instructions don't seem to work any longer. It seems as though I can't actually view the updated return without filing it first unless I'm just missing it. Perhaps some of the steps have changed since that time and they're outdated.
"Send page 2 of your 1040 only if the refund or owed amount has changed."
I did end up going in and adding the 1095 as if I were amending the already accepted federal return (though I understand I'm not supposed to) and the refund has indeed changed. However, there does not seem to be a way to print this updated 1040 or even view it without filing it... and when I decline to submit (because we aren't supposed to amend) and go to the home screen, it only shows the old, outdated, and incorrect return that I originally filed.
I tried adding a state tax (our state does not have an income tax so I didn't file one) and again, same problem -- can't view the updated 1040 without first filing.
