When is the payout expected to happen?
Sometime between Q1 & Q2 of 2019.
There are thousands of people involved. Completely pointless attempting to guess what all their motivations are. I can well imagine more than a few will want to cut and run. Plenty of others will choose to hold. It'll probably be five years before it's all done and dusted which is plenty of time to formulate your strategy.
I do wonder more about the Bcash as it's starting to look a little wobbly. Just over half of it has been claimed by others so in effect that's the equivalent of over 300,000 BTC ready to rock.
Either way I won't care if there's a dump. They waited long enough to deserve it if they want to.
Bitmain is shitting their pants right now, reason why they want to do an IPO which also includes their assets such as BCH holdings, whilst knowing that it will crash when those btc from mtgox goes into circulation.