According to the Kickstarter page, the game is expected to be released in May 2019, which would be consistent with Jeff's typical 12-18 month development time.
Also, don't take this the wrong way, Jeff, but your Kickstarter pitch definitely needs some work - both in terms of content and presentation. I've played almost all your games and have backed the Kickstarter, but someone unfamiliar with your work is not very likely to back this project. Have you thought about getting some help from a social media person to get the word out? I suggest doing (more) interviews, use Twitter/Facebook/etc to get the word out and describe the pitch in more detail. I see this Kickstarter as a chance to really step up the graphical quality of the next game series and expand the systems/content available therein, although this would likely entail hiring additional developers, which Jeff may not be comfortable with.
Finally, I'm not a huge fan of the visual perspective in the alpha build - I prefer the one in the recent Avernum remakes. I also hope we can zoom out our field of view.