You can apply using the 11-digit number in your vehicle log book (V5C) or the 16-digit reference number on your vehicle tax reminder. “If you prefer for it to start on the first day of the next month, you’ll need the 16-digit number from your tax reminder letter. This is only true if they have a valid SORN (Statutory Off Road Notification) issued by the DVLA. Recommended reading“Many owners keep their insurance active for peace of mind, and some storage facilities require proof of insurance as a condition of use.”Can you drive a SORN vehicle? “If your MOT expires while your motorhome is off the road, you’ll need to book a new one before it can be taxed and driven again.