We don't know the background story, but former chief developer Frédéric Devernay revived the Natron Github repository ten days ago and has been working on bugfixes and new features ever since. According to the current version of Github, a new release in version 2.3.15 is probably imminent.
Natron is a free compositing system for Windows, Linux and Mac that is very similar to the commercial Nuke. Not only in the Open Source community the program had many fans, but they were surprised 20 months ago that the chief developer Frédéric Devernay stopped working on the project and couldn't find a successor/maintainer for the further development.
It looks like Frédéric is on the ball again and there should be more information about the future of the program soon. After Fusion has been developed further unexpectedly, the world of stand-alone composers is now in a much darker state than expected at the beginning of the year.
;)