What’s your location string? Have you clicked on ‘Lookup’ to see if it’s recognized by Wunderground? The auto timezone setting hasn’t been tested comprehensively for international cities. If you specify your location string we can help you check what the issue is.
Regarding source code: the main repo is for official release, so 2.1.0 hasn’t been checked in yet because it’s not officially released. The separate repo is for maintaining intermediate changes, for example, the current 2.1.0-beta code is there. To compile 2.1.0-beta in Arduino, just grab the hardware profiles from the main repo, and use the 2.1.0-beta code from the development repo.