I don't believe the law has ever been revoked that requires anyone sending documents through a non-USPS service* to include the appropriate USPS postage cancelled with a pen along with their shipment
* excepting a point-to-point courier service for some reason
The USPS carved out a few exceptions, like delivering urgent mail. Gaming the system will get you raided by armed agents of the enforcement arm of the USPS.
AFAIK there are exceptions for express couriers, which is why you can still use fedex/ups to delivery documents.
...but you can delivery boxes...?
so put mail in boxes?
I mean, there's DHL, Fedex, and others...
I don't believe the law has ever been revoked that requires anyone sending documents through a non-USPS service* to include the appropriate USPS postage cancelled with a pen along with their shipment
* excepting a point-to-point courier service for some reason
The USPS carved out a few exceptions, like delivering urgent mail. Gaming the system will get you raided by armed agents of the enforcement arm of the USPS.