There was plausible deniability on the part of the voter/sender. Now there isn’t. Except I doubt that many people will actually know about the change/clarifica

There was plausible deniability on the part of the voter/sender. Now there isn’t. Except I doubt that many people will actually know about the change/clarification so they’ll continue to mail ballots and taxes at the last second. In a sane world, anything mailed “close enough” would be accepted. Or there’d be an explict 5-day grace period.