The exit polls for the UK election have suggested that Theresa May will be unable to hold onto her majority in parliament, creating the panic selling in GBPUSD that we have been planning for since Tuesday: https://www.fxstreet.com/analysis/gbpusd-trade-beginning-to-align-for-election-thursday-201706061411
Whether traders were able to capitalise on the opportunity would depend to a certain extent on which triggers they chose for their entries and at what point their four-hourly charts closed, as different patterns would arise. However, almost all should have been able to capitalise on this setup, which is still in play.
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