The contests are hosted by volunteers who have probably removed the tracks shortly after it was finished being judged. Those tracks are a HUGE chunk of sound taking up space on their hosting servers, so keeping them up after each contest may not have been feasible to most.
We're still in the middle of the current contest (7) with deadline for entries set at Monday 1/17... If you have a copy of the tracks, sounds like you won't have to wait until PMC 8