E911 for remote users who have offices with phones at HQ?

We have a client who are headquartered in No. Cal, but have 11 remote users, 7 of whom have physical offices with desksets at HQ. The entire company is on DID’s with local No. Cal area codes. The CEO has a deskset and a portable in Philadelphia and a deskset and conference phone in their office in No. Cal. All devices use the same extension numbers (last four) and ring simultaneously. Other remote employees have a similar setup and a Bria softphone on their mobile phone. They are adding International employees in Europe and Asia.

HQ setup for 911 is done, but now questioning setup as they have two buildings (ALI requirements?).

I would sure appreciate some input on this spread out E911 setup. I have watched and read several of Fletch’s articles, but they mainly address 1 phone one location scenarios. Doesn’t work here.

The FreePBX distro is 12.65. We are considering upgrading the client to 13, but PJSIP seems to really limit the above scenario with regards to E911.

Appreciate your insights or pointing to the right source.

Thank you!