After updating iPhone iOS version to 14.7+, Xcode 12.4 can no longer build to that iPhone device.
In Xcode when choosing a Build Destination (Product > Destination > [device] or from the UI dropdown shown below) the newly updated iPhone will have beside it (unsupported OS version):
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iPhone listed with "(unsupported OS version)".
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Can't Upgrade to Big Sur / Xcode 12.5
I'm stuck on Mac OS Catalina (old hardware) and cannot upgrade to Xcode 12.5 which requires Big Sur.
How can we add/update device support to Xcode to build to an unsupported iPhone version (iOS 14.7+)?