I uploaded a build using the Xcode beta, forgetting that you can't submit builds compiled with beta versions. So I updated to the release version of Xcode via the App Store.
With the Xcode beta, App Store Connect was accurately reflecting the build number (4.8.1). Now with the release version, Connect shows a build number of 5. I tried incrementing in Xcode to 4.8.2, and now Connect showed a build number of 6.
Has this happened to anyone else?