We've contacted Ubisoft to find out a little more regarding those "business reasons." We'll update if we hear anything.
Update: Ubi confirmed the Epilogue DLC is "slated to release only for consoles on February 26th." Perhaps Ormazd will bless PC users with a Feb. 27 release, but that's unlikely. Our query concerning the "business reasons" behind the decision went unanswered.
[Thanks, Vivienne; Via Big Download]