P.T. is now also gone on the PC store
While there are some reports that Konami’s P.T. demo, which was removed from the Playstation Store on PS4, was also not available for re-download, that is apparently not true.
Logging into the PSN on PC and showing your download list will still show P.T. and give the option to download to PS4:
Even if it’s not appearing on the PS4 download list, it’s still available remotely to download.