To be honest, I haven't been updated on this topic for a while, so I'm not 100% sure if these plans have been changed.
But back in June 2018, @MattScott announced that Fight Club would eventually be replaced by a new mode called "Riot", and possibly removed.
June 29, Matt said: "Spoiler: I am going to get rid of Fight Club and Open Conflict[...] FC will stay in until we fully release the new mode, and we see a significant drop off in FC players."
On June 30, he explained a bit more and said that there will be a new mode called "Riot" will be added to the game and eventually maybe replace OC and Fight Club
"Internally the new mode is being called "Riot". It will go to OTW long before we add it to production, and we can run it as a replacement to Open Conflict. ".
Here he also explained that he was a bit unclear in the post from June 29th.
And almost a year later, we got the new mode, Riot. So... what are the plans for Fight Club?
For me, Fight Club is one of the reasons I still play APB, and I see no point in removing it entirely. Though I can totally say that Fight Club is far from perfect, and has never been perfect. It needs a lot of changes and fixes, such as those disgusting spawns in Baylan, and boring mission objectives in Asylum.
What do the community think about this? And how can they make FC better?