[rsynnott]

> This could have been prevented by simply not changing things at the last minute.

No. For all the coverage that late arriving pre Election Day postmarked ballots are getting, they're a pretty minor factor; probably in the hundreds, not thousands, in PA so far, say. PA already had a rule that they couldn't start counting mail in ballots until polls closed; that's not new, and that's essentially what's causing the delay here, along with similar rules elsewhere. States which didn't have rules like this finished quicker, but these rules aren't new.