The election is nonetheless consummated because officials know there are X ballots to count, and they know there are X ballots to count because the proverbial ballot box is closed. In short, counting ballots is one of the various post-election "administrative actions" that can and do occur after Election Day (cite elided) Receipt of the last ballot, by contrast, constitutes consummation of the election and it must occur on Election Day.
If your state permits ballot receipt after the close of the polls on Election Day it is at risk of its certificate of electors being ruled void.
Now this is one Circuit but it does not carry an injunction but rather is an immediate remand, so absent an appeal directly to the Supreme Court (1) it stands and (2) it only binds the 5th Circuit States, at least in theory.
However, it now presents an extreme risk for states outside that circuit who might choose to permit ballot receipt beyond the close of the polls on the 5th of November.
I expect one or more of them to try to run this up the pole to the Supremes, but it is quite-clear and cites plenty of precedent including both the Constitution and long-standing Federal Statute, neither of which has been amended.