I know it's early, but curious when we might start to see used or CPO 2018s on the market?
I like the 6yr/72k warranty but hate the depreciation on a new car.
In most cases, I'd expect to see them in 2-3 years, when the off-lease cars start to make their way through the auctions. However, that will depend on how many are being leased.
As far as what sort of warranty they'll add on, it's hard to say. BMW used to (and may still) offer 4yr/50k factory warranties on all their cars, which became 6yr/100k (from original purchase date) for CPO. The CPO extended period had the usual exclusions, and also had a $50 deductible. Since an off-lease 2018 VW will still have (roughly) 3/36 of the original warranty remaining, they may only extend it for a year, if that.
I'll keep my eye out at work for updated CPO docs when VW releases them, though I doubt I'd see any solid CPO information earlier than when they advertise it to the public, so don't hold your breath.