TPG says the bus to PHL will be sterile and
arrive airside:
Upon arrival in Philadelphia, the bus will pull up airside (past security) and you’ll disembark into the terminal. Your checked bags will be automatically transferred to your connecting flight, and you won’t need to reclear security.
This is very interesting and different from the UA ABE-EWR bus, which arrives landside. Is there any precedent for a passenger transport vehicle on public roads (not within an airport fence) being considered sterile by TSA?
Presumably there will have to be a protocol to not disembark airside if there has been any irregularity during the drive in which any bus door (including emergency exit) has opened. Perhaps physical tamper-evident seals will be placed on all bus doors and windows after boarding and then inspected before letting anyone/anything off airside at the destination.