The hotel in the movie was originally scripted to be the "Astoria Hotel" and shooting took place with the actors calling it this. However, upon realization that such a hotel actually exists and fearing legal consequences, the film's creators came up with and recorded the cover up name: "Castorian Hotel", which was easy to sync with the actors' lip movements during sound editing.
Filmed in 2014 and 2015, but only released at 2017.