Have you tried calling Nissan directly, and explaining that? There are now rumors of a possible lease extension, and also a possible discount, to get current Leaf drivers into a 2018 Leaf. Without something more solid than rumors, though, Nissan will lose a lot of Leaf drivers this year.
I have already extended my lease 6 months, ending in April. More would require the continuing lease fees and more car registration fees.
I was hoping the Goshen keynote at the Detroit Auto Show Jan 5, or the speech the week after would give clarity. It didn't. Only "in the near future". Instead the Nissan press machine gives us a weekly chapter of an adoring biography of Carlos Goshen.
I really wanted to be a Nissan customer. Experience and early to market risks earned that. Not now. I have a TPW and delivery date before Nissan says anything.
Added later: I would point out that the first "spy shots" for the Bolt appeared 17 months before production began. If given a fairly similar chassis and software system , maybe they are working on a shorter time frame... 8 to 10 months before production?