Tell me about it. When I decided to not opt for the lease w/buyaback option I knew my resale value would be down due to incremental improvements over the years, but I didn't expect to see the 100D and AP2 come only a few months after taking delivery.
This is precisely why I took the financing with buyback option when I got my car 6+ months ago. I wasn't thinking about autopilot in particular, but I was thinking that there could some unforeseen technology improvements that would crash the resale value, the most likely scenario being that Model 3 exceeds expectations enough to depress demand for Model S.
I'm not sure if it was in this thread where someone complained about being "blindsided," but I was among many owners who paid 50% more for my Tesla than for any previous new car. This made me want to exercise a lot of diligence before taking the plunge, especially with new technology that might have reliability issues. That search led me quickly to this Forum as an excellent resource. Pre-purchase, most of that diligence was related to the drive unit and pano roof problems. While there was no hard data a year ago, I concluded that efforts had been made to solve those problems. 11,000 miles in, so far so good and we are delighted owners.
The buyback option was was probably introduced as a hedge against reliability problems for brand new technology in 2012-13. By the time I took delivery in April 2016 I decided it was more a hedge against unforeseen technology improvements. My guess is that Tesla does not believe it needs the buyback option for reliability assurance anymore, and this did away with it a few months after our purchase.
With regard to autopilot, it was not a high priority when we ordered, and it was not included in our order until we read favorable reviews and took an additional test drive with it. Now that we have it, we use TACC a lot, Autopark some, and Autosteer mainly in congested traffic situations. As we probably use the Autopilot features less often than the average owner on these Forums, I'm not that upset about missing Autopilot 2.0 by close to a year in terms of improved functionality over Autopilot 1.0.
However, if Autopilot is close to Level 4 functionality during our April-June 2019 option window, that will be a point in favor of exercising that option. The other point would be substantially improved Gigafactory batteries in terms of range or charging speed.