According to this little excerpt in Deadline’s Brad Inglesby post, it claims it’s happening this fall:

“Pruss helped Ingelsby get his Low Dweller spec seen around town, and this is his third project with the writer, after Hold On To Me, which James Marsh is directing this fall, and The Signal, which is being developed by Paramount.”  [My emphasis]

It’s still listed as “optioned” on IDMbPro.  And if you look at James’ projects in development he has another “optioned” and one at “script”.  Other than that he’s got a film in post production at the moment.

I guess time will tell.