You can probably figure out the lease numbers. Just look at lease numbers for another car with a comparable value without any incentives. You know early buyers will be paying near MSRP purely because of supply and demand.
If I didn't' already own a G1, I'd be in the market for a heavily discounted G2 near mid to end of 2017. If I really wanted a Bolt, it would be 2019 when those should see heavy discounts. If the car is a dud and demand is low, expect the heavy discounts sooner. If the demand is high then they may be like saturns (or hondas, subarus, toyotas) sold with very little discounting.