Dug hard to find a map of Primary Entry Point Stations. Not readily available.

Primary Entry Point (PEP) System. Defined in Section 11.2, 47 CFR 11.2, as “a nationwide network of broadcast stations and other entities connected with government activation points . . . used to distribute EAS messages . . . formatted in the EAS Protocol . . . , including the [Emergency Action Notification (EAN)] and EAS national test messages” that includes “some of the nation's largest radio broadcast stations,” as approved by FEMA, and is “designated to receive the Presidential alert from FEMA and distribute it to local stations.”

http://pages.iu.edu/~djwild/pep.jpg

>>3051071

Better info attached in:

NAWA_operations.PDF

Here is how POTUS uses the EAS system:

The national-level EAS is activated by an order from the President to the White House Communications Agency (WHCA) duty officer or the President’s Communications Officer (PCO) through the FEMA Operations Center (FOC) or FEMA Alternate Operations Center (FAOC). The FOC/FAOC authenticates the request and establishes the Primary Entry Point (PEP) conference. At the request of the President, FEMA distributes Presidential Level messages to the PEP stations. As the entry point for national-level EAS messages, the PEP stations have a National Primary (NP) EAS designation and are monitored in turn by other AM and FM radio stations; TV broadcast stations (audio only) and cable systems (audio only) in the hierarchical chain. The 83 National Primary PEP stations are listed in figure E.1.'

List of PEP, battle hardened radio stations that rebroadcast the message.