Have market-makers already voted to "Leave"?

Early voting in the UK EU referendum is closer than most have predicted. Regardless of the outcome, one takeaway is the readiness of our new, highly regulated financial markets to deal with a surge in volatility and the impact on trading volumes. Ahead of this potential risk-off event, warnings have been issued by some of the markets leading financial institutions and traditional market makers that "in the event that extreme market moves occur in an environment of limited liquidity, our principal spreads may widen for both electronic and voice trading, liquidity may reduce and prices may turn indicative (i.e., non-trad-able) for periods of time". Yes, non-trad-able.
"In the event that extreme market moves occur, giving rise to limited liquidity in certain currencies, we may not be able to fill limit orders or take profit orders at the levels, or using the methodologies, expected in normally-functioning markets". Presumably "stop-loss" orders may similarly be good in theory only?

Regardless of outcome this may be the enduring legacy, that markets cease to function in uncertain times. At the time of writing, normally ultra-liquid markets like the GBP has fallen 5% in a matter of seconds, before partially recovering. Half a world away, Australian bond futures are trading on less than 10% of regular volumes.

At least we can't say we weren't warned.