There has always been a select number of races that David Lewis has planned for the Dropzone Commander, and from previous discussions with him over the years, that number is capped out at 8 distinct factions/races. These of course are a ways out in the future, as he does not want to add new races to with every book release and progression of the Dropzone timeline.
This was the latest conversations that brought up the number of races for the game, taken from facebook, where Solomon Chang had dinner with David Lewis at the Las Vegas Open.
via Solomon Chang on the facebook dropzone community group
"There's a lot of whispers on the forums that the Scourge are actually running away from a bigger threat. Any thoughts on that?"
"No. I've already planned out the storylines of the current races for the next two years, and while there will be a shocking revelation about the Scourge, it won't be that."
(Okay fine, just like a typical British tabloid.)
"Any spoilers on new races? How many races will DzC have?"
"No, no spoilers. Dropzone Commander will probably cap out at 8 races, but most new stuff will simply be additions to current factions." "