If the UK chooses "Brexit", most analysts agree the Pound will lose 20% of its value almost immediately. Even if the UK doesn't "Brexit" lower prices are ahead. From a fundamental perspective economic news in the UK has been subpar. The PMI numbers for manufacturing, services and construction came in below expectations earlier in May and recorded a lower than forecast number.
Although the BOE voted to leave rates at 0.5%, the currency will be out of favor moving forward.