The Kazakh central bank might be on the other side of your trade
Bloomberg has an brief story after speaking to the central bank leader of Kazakhstan.
Evidently, they're actively trading it the $30.5 billion in FX reserves managed by the bank.
Governor Daniyar Akishev said the central bank opened a long position at 1.4350 in GBP/USD "on the expectation of market volatility" ahead a few days before the referendum and "fully exited" the position at 1.4920 a day before the vote.
They don't offer any indications of the size of the trade and the reporters and editors seem to be struggling with what actually happened because they report this:
"The former Soviet republic's central bank bet against the currency before Britain's surprise decision to leave the European Union last month," they wrote.
Taking profit isn't exactly a bet against a currency.