I think the identity is connected to what key pair you control / what private key you have on your phone. F.x. I installed a while ago Signal on my phone and r

I think the identity is connected to what key pair you control / what private key you have on your phone. F.x. I installed a while ago Signal on my phone and recently went to another country where I used a different SIM card (hence a different phone number) and I could still use my Signal app as usual.