alt Hacker News> They've already gotten a ruling that ballots received after a cutoff do not count
Watson v. Republican National Committee seems to be the opposite of what you state: ballots received after election day can be counted provided they were postmarked on or before election day.
You're right, the 5-4 SCOTUS ruling this summer reversed the appeals court ruling, preserving states' rights to set laws that permit counting postmarked ballots -- if postmarked in time.
Curiously, the USPS changed when it postmarks mail this year, resulting in postmark delays. In Washington state, the number of ballots rejected for being late is up 32% compared to 2024.