Sold London Flat, Need to Transfer Currency, Should we Wait Until After Brexit Vote?

California exchange rate concept

We've just sold our London flat so we have around £260,000 that we want to transfer to the USA where we live (California).

We've been watching the pound/dollar rate and it seems like we should transfer the money soon.

However we're also thinking we should wait until after the Brexit vote in June.

We're also thinking about transferring half before the vote and half after.

What is your view?