Cancel the Transfer on the Iphone 12 Pro Max?

When you startd h transfer on the old phone, soin the iphon 12 pro max, in my case, the transfer screen takes over the entire device. So i was waiting for a phone call yererday, and that phone call never arrived. It turns out it doesn't block foncols. Those are the only things that comes in when you're doing the transfer. My phone still kept buzzing, but just nothing was happening. I feel like there should be some kind of explanation of what happens whenyou're doing this transfer on theold phone? If you're waiting for an emergency, will you get that phone call or something else?