www.theguardian.com/politics/2016/jun/23/referendum-night-when-to-nap-and-the-results-to-watch
Looks like expectations are for remain to be in the lead until about 3am but if leave have a vote share of 45-50% at this stage it will be a close run thing. Less than 45% and remain have done well....and we can all go to bed!