Crunch time or not, the client is relying on you to catch all those little details and do it correctly.

Getting software changes at this point is nearly impossible, even when it is critical. State software changes are way down on the list of "things to do"

Make yourself a "must do" final checklist before e-filing and you'll have an easier time of it, and by April 15th or 18th, it will have become second nature for you.

Lists are boring, but they work, speaking from practical experience.