70 plate Transit camper - lights keep coming on

[DKL]

We're having a lot of issue with a brand new Transit where the lights keep coming on on their own. Usually in the middle of the night on a camp site which isn't very popular.
Ford have had it twice and "fixed" it but it returns. It only happens after a long run hence when we are away. It's been checked on the drive for a few days and was fine but reoccurred after a trip north.
With the number of Transits out there it must have happened before, anyone any ideas?

[sherman]

Follow home lights?
Is it just after you lock up for the night?
You can change the setting yourself.

[DKL]

I don't think so it's too random. It may be connected to it but not part of it's usual function.
I haven't switched the function off to try as I'm not really looking for a work around on a brand new vehicle but it would be worth knowing if that prevents the problem certainly.
Only seems to happen after a long run and sometimes having sidelights on will stop the headlights coming on but sometimes the headlights come on anyway. There is definitely a fault they just need to find the wretched thing.