V5 - Light 4x4 utility

What is meant by Light 4x4 Utility on the V5 for my defender 90?
Does it mean 'pick up'?
It used to be a pick up but i put a roof on it with windows and seats in the back.
Should my V5 be changed now to something other than 'light utility'?
No seat numbers are specified on my V5, just blank.
?

Wouldn't worry about it so long as you tell your insurance co. how many seats you've got.