Your valuation doesn't hold: you're not buying a finite state, Bitcoins will keep circulating beyond that distribution. You're buying into a company, not into a finite distribution system set to end at a finite time. That means the cash FLOW is the important issue. Just like in real life the valuation of a company is not locked to how much fiat is in circulation (as we all know, cash circulates around).
I agree that there is a link right now, but they are already generating revenue that isn't mined, that should give you an idea of possible expansions they might explore. However, there is a huge risk from the shaky grounds the business is standing on: legal, logistic and so on. There is not much liquidity to move 100 shares so the price we see is still "pretend" regarding current price level seen on exchanges. I totally understand folks hedging their position by selling some shares "while there is some kind of support at said price level".
Again, this has been said much but should be kept in mind by all in here:
Only invest what you can afford to lose.
Discl: I am Long AM, but there's a risky road ahead for many, expect many bumps in the road with weak hands dropping here and there.