Has USPS announced any limits?
It arrived in my state, about a 45 minute drive from me on Sunday, and it is not expected to arrive until Friday. presumable sitting in a warehouse in a queue of things to go out
It's possible we've just been unlucky and these packages are lost, but it could also be indicative of a larger logistical problem with USPS.
My daughter sends books via media mail to a friend in suburban NYC. For basically pocket change, they get there in 3 days or so.