I'm a bit cautious about AM having large btc reserve:
a) on the 'saloon' FC talked about negative balances, whatever he meant it's reasonable to assume AM hadn't a lot of btc in mid-July.
b) since then the whole network mined around 250k,
c) to mine ~60k would require almost 25%
Not viable.

Of course FC could have been engaged in speculative and highly rewarding transactions.