Yes I've gotten all the way to the transmit returns now button with the lock icon, warning message about how it can't be cancelled and everything. And apparently you can because I swear I've redone the filing steps about 5 times and at no point does it ask/ make me enter my agi. If I use the original, non-amended agi, then won't that cause problems? They ask for it (or are supposed to) for a reason, I'm sure it has to be the actual correct version.
