USPS, as well as the local, state and federal agencies in the storm damaged areas, are still in search and rescue mode. There are employees in Beaumont postal facilities that cannot be reached. Other than search and rescue, the instructions to USPS employees is to shelter in place. Damage assessment hasn't even begun in much of the Houston area.
Mail processing is taking place in Austin and San Antonio. Mail that can be transported for delivery is going out, but mail for the affected area is being staged, or held in Dallas.
The Houston processing facility is going to attempt to reopen Thursday. There is no estimate of damage to the facility, how many employees can reach the facility, or what transportation into the facility will be available.
Damage assessment and work on contingency plans will begin as soon as safety and logistics allow. The Inspection Service and USPS undoubtedly lost a lot of their vehicles.
If newspapers have print editions that can be entered at their local post offices, that's great. But realize that some delivery will be delayed more than usual. If the edition can't be entered it's probably best to stage it (hold it) somewhere. We should know more beginning next week.
– Mike Hodges