So as a bit of a postmortem:
I contacted Tesla on Dec 15th asking them to take the car back due to mounting annoying issues.
To my surprise the called me back on the next business day and since the process was already started back when they received my original notice in the Summer, I am all approved.
The next call I got was Dec 26, they told that all is ready and they'd like to have the car back by the end of the week - this came somewhat unexpected since I was fully prepared to fight them for a fair price based on other reports. The only point of contention was the tax credit that I was not sure I am eligible to file for when the car is no longer in my possession. While originally we agreed they'll include a note in the release that they'll cover this, in the end that was hard to do, so instead we settled for the email from service manager that said they are assuring me I am eligible for the tax credit and if IRS would disagree at any point, Tesla would reimburse me for the tax credit value and any penalties imposed.
Today, Dec 29 they came to pick up my car, the paperwork (unsurprisingly) said that they are buying my car as a goodwill gesture and not as any sort of a warranty claim or any unconformity. So I guess it'll join the CPO fleet soon?
This I think greatly highlights that you really should file necessary lemon law notice even if you don't plan to follow it all the way through at the moment you meet the criteria. Not only my service drastically improved very soon after that, if you change your mind about the whole matter later, the long parts of the process likely have already passed in the background.
Surprisingly I fully assumed they'll bring me the check, but it's coming in the mail at some later date, huh?
Note to future buyers, if you are looking at a deep blue model X 100D with just over 5k miles on the odometer, mid-March 2017 production, red tesla-logo decals on the wheels - double check passenger side FWD window operations, some steering wheel/car shaking at 65+ mph and integrity of driver door's insides. Also know you'll be getting a former unicorn
I guess I should put a VIN here too?
The car was a dream to drive when it was working properly and I am sure going to miss that part of it! Here's hoping QA would drastically improve in the future.