I think that–particularly since the futures contracts will be settled in cash–this current spike in BTC price as it relates to futures trading on CME/CBOE doesn’t make any sense. The institutions that are now given legalized/regulated access to Bitcoin cannot (publicly) and will not ever need to hold a single Bitcoin to bet on the future price. Therefore, if it were me, I would sell some amount of BTC on 12/18, take the profits and funnel them into alt coins. My two cents.