A report of a new patch rendering P.T. unplayable, even if the game is already installed on your PlayStation 4, is circulating the internet.
A Reddit post from user PopulusTrichocapra was posted on r/SilentHill a few days ago, claiming that they couldn’t access P.T. (the “Playable Teaser” for the unreleased Silent Hills game) on their PS4 with an accompanying screenshot of the locked game. The picture shows that this is version 1.01 of P.T., that the latest update occurred on October 22, 2018, and that the application is ineligible to start up.