This has been covered before
If your vehicle is going to be off the road. (S.O.R.N.)
If you are not going to use your car, going to the UK on an extended stay for example, you can obtain a rebate of some of the road tax unused during your absence or delay having to renew your road tax.
Before you go away, or as soon as the vehicle is off the road, fill in a form TOM 12 and take it with your log book to the Department of Transport Offices or Citizen Service Centre.
You will have to nominate a place, off the road, where it will be kept during your absence so that it can be inspected.
You should now take your bank IBAN number with you as any refund is paid directly into your account. On your return re-tax the vehicle.
The notification cannot be backdated and is similar to the Statutory Off Road
There is a downloadable for on this site
http://cyprusdriving.net/road-tax-circulation-licence/