As evidenced by the lastest video, the project is making leaps after initial delays caused by the notorious Denuvo anti-tamper tech. The team are now able to synchronise parachutes and jetpacks between players and can run a multiplayer server for an hour without a crash. Swooping about is half the game, after all.
Catch is, when the mod is ready for public testing, it will require you to own Just Cause 3's DLC to work.
The main menu—plus server browser—are next to be completed.