Since the 20th of April, 2021 my apps have been sporadically (1 in 2) failing for the ITMS-90725 issue and is explained as follows:
ITMS-90725: SDK Version Issue - This app was built with the iOS SDK. All iOS apps submitted to the App Store must be built with the iOS 13 SDK or later, included in Xcode 11 or later. Further, starting April 26, 2021 iOS apps submitted to the App Store must be built with the iOS 14 SDK or later, included in Xcode 12 or later.
Which is very odd as I'm using XCode 12.4, has anyone else experienced this issue and/or fixed it?