According to the LA Times, the actor, director and main creative force behind the original film is currently meeting with directors to helm the David Agosto and Ken Kaufman (Space Cowboys) penned follow-up. However, nothing is yet confirmed and these are just talks so Stallone could conceivably end up helming.
The sequel has been in development since the original film premiered last summer, as Stallone has been quoted saying he has "had an idea ready to go," that will be "quite radical." Evidently, in the sequel he wants to emphasize new characters roles versus the veterans.
And, well, an expendable cast and director isn't tremendously surprising news, considering the name of the movie and all.
Source: LA Times