Exactly what the question states.
How do you Keep your source build in sync with the latest release on github?
Say you got source and dependencies for 4.9 built it and started using it, and after sometime 4.10 comes out then how do you update your current sources to 4.10 using git?
Or is completely new build is better than updating? if it is then whats the purpose of using version control?
I want to learn and do some custom stuff in the engine like calling java api in android etc, So I want to build the engine from source but I have 4.8 sources.