On your V.5 section 7 changes:

Wheelplan / Body type (20);

Put VAN (if it says Minibus in D.3 body type)

In No. Of seats (25);

Put 3.
No of standing places 0

If DVLA want to inspect you will hear from them.

Don't know how long the changes will take to appear on The insurance register though.

You might have to insure as a minibus then change later.

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