iOS 26 Dual SIM bug: changing a contact’s default line and dialing immediately places the call from the wrong SIM (caller-ID leak)

Device: iPhone 16 pro max

iOS: 26

Dual SIM setup: Personal + Work (both active)

Issue:

When I change the “Default Line” for a contact and immediately place a call from that contact card, iOS almost always places the call using the OTHER SIM than the one I just selected.

Steps to reproduce:

1) Open a contact.

2) Tap the line label (e.g., “Default”) and set SIM [Personal/Work] as the default line for this contact.

3) Immediately tap the phone number to start a call (without closing the contact card).

→ The call goes out from the wrong SIM.

Expected result:

The call should use the SIM I just set as the contact’s default line.

Actual result:

The call is placed via the other SIM. The newly selected default is ignored if the call is initiated right away.

Workaround:

If I close the contact card and reopen it before dialing (or initiate the first call from Recents after setting the line), the correct SIM is used.

Privacy / legal impact (high severity):

Because the call is placed from the wrong line, my **private** number’s caller ID is disclosed to recipients who should only see my **work** number. This is an unintended disclosure and, depending on jurisdiction, may be unlawful (e.g., GDPR/ePrivacy concerns).

Question:

Is this a known iOS 26 regression in Dual SIM handling? Any official fix?

Thanks.