I think I need to make it clear, when I said 2017MY it is the model which will be built for release either late '16 or early '17 as is usual for cycle plans.
The "2016 battery refresh" I asked him about (and which he denied any knowledge of) was this higher capacity battery update everyone in here is getting excited about, this is what I wanted cleared up as we are about to pull the trigger on an i3 and didn't want to have a two month old "out of date" model.
BMW has been asked this before during various interviews, and the consensus was, if it is economically feasible, they would consider offering this as an 'upgrade' option later on. My guess is that, no, unless you had a problem with the existing pack, most people would not find the exchange a viable endeavor. Whether that is even reasonable is unknown. The size of the pack is likely identical. Also, keep in mind, a larger pack might require logic updates to tell the computer the battery pack size so it could display ranging info properly along with time to charge. And, unless they enlarged the on-board charging circuits...charging a larger battery would also take longer. So, it's not just swapping the battery packs (from what I hear, about a 4-hour job). BMW has come up with plans to recycle used, but still viable battery packs, but how much, if any, credit they give to the customer is still unknown, since any pack replacements now going on are all under warranty, so as far as I know, nobody has needed to purchase a new pack, yet.