Are graduate school applications processed before the submission deadline? I will be applying for PhD positions starting in fall 2016. Most of the application deadlines are in January. If I send my application now, will it be processed immediately? Or are the recruiters waiting until the deadline has passed? This probably varies somewhat per geographic region (and university, and department) but I would be mostly interested in UK institutions in the STEM fields.
In my experience (in a large public American computer science department), review of applications begins as soon as they are submitted, but no decisions are announced until well after the posted deadline.  Reviewing graduate applications actually takes significant time, and admissions decisions are based at least in part on comparisons with the rest of the applicant pool.

My university actually forbids announcing admissions decisions before the application deadline.  Other universities/countries may have more relaxed policies.