Yes of course the electorate can change its mind when the next vote comes around. That's exactly what has happened. The first vote (in 1975) people voted remain. After 41 years experience of being in the club, when a second vote was granted, people voted leave.
It would make sense, after we've completely left so people can see what that's like, to have a third vote to see if the people wish to rejoin. This could happen after a reasonable period. It doesn't have to be 41 years again, but it could be at least 5 or 10 years after we've completed the leaving process - otherwise we won't have given that a fair test. Also it would require the EU to agree that we could rejoin if the people voted to do that.