FPBX v2.9 w/ all updates applied
Yealink endpoints (T26, T20)
When dialing to an internal extension with FollowMe ENABLED, FPBX uses the dynamically generated setting of “callerid=device " found in sip_additional.conf. On the calling party’s telephone, the caller briefly sees the EXTEN number and then the display quickly changes to " EXTEN”.
When dialing to an internal extension with FollowMe DISABLED, FPBX uses the setting Display Name that is configured in the Extension Settings page and ultimately is located in voicemail.conf.