Now we have remote field in dialog-info of NOTIFY request. This make possible to show who is calling (Full name, if PBX has it) on numbers user had set as BLF on user's phone.
It's time to add local field, so user will see not number but Full name of callee (BLF Visual Alert screen on Yealink phones).
P.S. And check, please, why PBX don't send identity display for calls from trunks?