(iii) Proposed provisions specifying that the USPS shall not transmit mail-in or absentee ballots from any individual unless those individuals have been enrolled on a State-specific list described in subsection (b)(iv) of this section with the USPS pursuant to this subsection.
I'm not sure how post offices in these states could even respond.
By laughing and ignoring it, having the Governors and Attorneys General of those states countermand it with their own executive orders / statements, just straight up saying that this is plainly obviously unconstitutional.
They could then also threaten legal action against anyone at the USPS who does not listen to them.
Its yet another Constitutional Crisis, any way you look at it, but, its not like there's just no possible response.
The President is straight up demanding that Postal Workers engage in a conspiracy to, amongst other things... tamper with people's mail.
So, any manager or supervisor who orders that be done? 30,000 counts of mail fraud, you're arrested and go to jail forever.
Set up a state tip line for USPS workers to report anything like that happening.