According to this site, since Android 8, build numbers have a certain format. However, I have an Alcatel 5030D_EAA with Android 10 with a build number 01011
What should I think of that?
The reason I ask this, is because I have some Bluetooth code in my app that does not work on this phone, but does work on many others (including with newer Android versions).
That site you have linked to explains the build number of Android Open Source project (AOSP). AOSP is the base of all Android versions, however (except for the Google Pixel devices) AOSP is not used directly on Android phones. Instead each manufacturer adapts AOSP to each device and additionally usually a lot of manufacturer specific modifications are applied.
Therefore most Android builds you can find on real phones don't follow the build number scheme proposed by Google in AOSP.
As long as the built Android OS in the end passes the Google Android compatibility test it can be sold as Android phone with pre installed Google Android Apps (especially Play store).
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