UK Car In Fuengirola

You can use UK driving license for six months, this firm can insure in UK plates after the 3 months  https://www.abbeygateinsure.com/en/

But if you want to move and keep the car in Spain, then its gets complex, you need to import the car with official paperwork when you move, personal effects not subject to duty when move, providing you have lived in UK for 12 months, or will be subject to import duty Spain now a third country. You cannot do latter the car can only be used for 6 months on UK plates, then when change you will have to import. 

You really need the help of an agent to sort all this, you also need paperwork for all your personal goods to avoid import VAT, you will need for customs at the port. 

Look at some Upsticks videos YouTube and look at their site. https://upsticks.es/

https://www.ageinspain.org/post/moving-to-spain-customs-and-vat-rules-for-importing-personal-effects