With this release, drone is now apache-licensed. From what I've been able to find, the developers have been active in other discussions but avoided the topic of why they went open-source when drone wasn't.

A few developers that forked Drone into Woodpecker CI when it stopped being open-source are anticipating another "rug-pull" in a few years with Gitness. I'm a bit skeptical myself, but Harness does have other open-source projects and Drone's decision to stop being open-source predates their acquisition.