It's an interesting tactic. Not sure the Li market is mature enough for it yet but it could get there one day. We know it works for something like gold.
I don't necessarily disagree with what you have said. But the flipside of the coin is that end users want surety of supply (whether they then go change their mind is a different matter). They will want to lock in contracts to ensure they don't have downtime in their refineries.
This is complicated by what I see as a dichotomy of phases. At the moment there is probably enough supply around to meet demand and year your option works. Push out 2-3 years (especially if prices remain low atm and curb investment) and demand starts hitting the parabolic phase and their isn't enough supply, end users aren't going to want to be caught with their pants down working on a model where they have been buying feedstock from the spot market.
IMO
A40 Price at posting:
16.5¢ Sentiment: Hold Disclosure: Not Held