Hitman developer IO Interactive has admitted that they may not hit the monthly release schedule for their planned episodes.
In a post on Twitter, IO has stated that while they are "aiming for a monthly release" schedule, that planning is subject to change. This first came to light when the first Elusive Target release was delayed from its planned date of March 22. A tweet from the official account over the weekend throws the dates of future releases into doubt as well.
Honestly, this shouldn't be a huge surprise. Unless the content is already feature complete and ready to ship, delays will happen. Be that as it may, that doesn't make the folks who have bought in to Hitman's episodic plan any happier.
It's something anyone considering the Season Pass should keep in mind. If you're not willing to pay up front for content that might be delayed, you should probably consider waiting for the full release of the game, currently scheduled for January 2017, although that date could obviously be affected by any other delays to content.