DavidR
5
In all honesty that is an insignificant part of the build number, 9.0.2006.(not 2600) people generally don’t refer to (or even see) that element. Program updates taht are downloaded are only really found in the first three parts of the version/build number 9.0.2066.
EDIT: if you check the file properties of the avast executables you will probably find that they too will be 9.0.2006.159 as most of mine are. But avastui.exe is 9.0.2006.160 though the main avast service avastSvc.exe is still .159.