I'm waiting for my X 60d that might deliver end of sept or beg of oct. I don't want to miss out on 2.0 and for some reason I feel like beg of year will have better resale then end of the year (oct 16 vs Jan 17). So I have already talked to my parents about running numbers on a almost new X trade in if 2.0 is released. Basically exactly what you called about.
Taxes would almost wash out because you pay taxes on difference only in GA. And you would get two tax credits if they are still available. And tesla gets two sales and makes money on trade in (I don't care about this but some people on here care about tesla more than themselves for some unknown reason).
Let's say you take a 20% hit or $20,000 to make math easier. 7,5 is recouped in tax credit. And rest will be "cost to upgrade". If someone is willing to pay $20,000 for a .1 second faster car. I'm willing to pay half that for 2.0 hardware and a 2017 vs 2016 car and I would get to drive an X in the mean time.
Not best financial decision of my life but compared to canceling my order ($2500 additional lost) it's not that bad.
We will see but definitely something I am considering. Thanks again for your post.