caller ID on dial. The default caller ID is the caller's caller ID. And Twilio's UK documentation

says inbound calls receive the originating caller ID and outbound UK calls preserve the caller ID

sent. So in principle, John 07700, your 0114 Twilio number, Twilio forwards to SIM 2,

your iPhone displays John 07700. That's precisely what you wanted. There is a caveat. UK carriers

apply Ofcom CLI validation. Twilio notes that invalid non-dialable caller IDs can be blocked.

But passing through the genuine originating UK caller ID is fundamentally different from

inventing spoofing a number. Two, and yes, Twilio can effectively do a dissonance.

This is the interesting bit. You could give Twilio another number or potentially use the

same number with logic based on the incoming caller and recognize your normal number.

You call iPhone SIM 1 Twilio.

Twilio recognizes your CLI.