UPBGE (Uchronia Project Blender Game Engine) is a fork of Blender created by Porteries Tristan (a Blender Game Engine developer) and some of his friends in September 2015.
It's an independant branch and its aim is to clean up and improve current BGE code, experiment new features, implement forgotten cool features that currently exists but are not merged to the official Blender trunk, and try to make the BGE a more powerfull and a more fun engine.
Its development cycle is based on a month: 3 weeks to add new features, and 1 week to fix bugs. Then a new release is made available for download.
Regularly, the UPBGE merges the official Blender new patches, to stay up-to-date with the last Blender evolutions.
The UPBGE team is composed of volonteers, BGE users who are interested in the game engine development, a web developer, and a communication manager.
The team message: We hope that new users will join the project, and maybe help us to test new features, report bugs, give us feedbacks and ideas to improve UPBGE (https://github.com/UPBGE/blender/issues), and that new developers will join the team to help us and to have fun coding shiny things for the game engine.