[jjav]

> That hasn't been the case for Signal for some months

Wrong. Because:

> You still require a phone number for sign up for Signal

So, they have your phone number. What is displayed is irrelevant.

If they have your phone number (which they do), they will have to disclose it for any subpoena/NSL, so they do.

[Marsymars]

Please see the sibling comments, I feel this has already been addressed.