Issues like this really highlight the gambling side of forex.
As things stand now, the referendum is too close to call and could easily swing either way. A clutch of terror attacks or trouble with asylum seekers on the French side of the tunnel would encourage a sizeable number of voters to “pull up the drawbridge” and vote to Brexit. The “In” campaigners have a minor problem in that Cameron has a bit of a trust problem and his opponents are using that against him.
Biggest problem in trying to guess which way the vote will go is the apathy of British public. Turnouts for recent elections have been abysmal and if this vote is the same, the likely winners may be the side that manages to mobilise their supporters best.
Im not averse to trading in the days and weeks before the vote, but unless I see some evidence of a clear winner I wouldn’t trade sterling on election day at all