Could someone using Dual SIMs please test this scenario? If you’re on a FaceTime Audio call, will a call to either SIM phone number go through? Additionally, will it make a difference if the FaceTime Audio call has it’s “Caller ID” set to one of the phone numbers in use by your Dual SIMs, (this setting is found in Settings -> FaceTime -> Caller ID) and the incoming call is on the alternate SIM line? I understand the current limitations of Dual SIM on an iPhone. Per Apple: When you're on a call, an incoming call on your other phone number will go to voicemail, if you have voicemail set up with your carrier.* However, you won't get a missed-call notification from your secondary number. Call Waiting works for incoming calls on the same phone number. To avoid missing an important call, you can turn on call forwarding and forward all calls from one number to the other. Check with your carrier for availability and to find out if additional fees apply. In this case, is FaceTime Audio considered a “call”? Essentially, I’m looking to always have the opportunity to answer an incoming business call, even if I’m in the middle of a personal “call”. So if I strictly use FaceTime Audio for personal “calls” then I’m hoping the business call will still ring through. The only exception would be for personal calls with people on Android phones but frankly that is rare in my circle of friends and family. While it might sound like I’m overthinking this, my phone is essential for business and I spend an extraordinary amount of time on business calls. If my business line can’t ring in, I can’t do business. However I really want the ability to drop to a single device using Dual SIMs.