It seems that the warning message is not up to date.
I think It should be:
ITMS-90725: SDK Version Issue - This app was built with the iOS 15.5 SDK. All iOS apps submitted to the App Store must be built with the iOS 16.1 SDK or later, included in Xcode 14.1 or later."
(cf https://developer.apple.com/ios/submit/)
see also https://stackoverflow.com/questions/75772955/itms-90725-useless-error-message-since-it-contradicts-itself-apple-upload/75788891#75788891
You should be fine until April.
This is just a warning for now.
gkueny
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