Moving to spain permanently as a UK employee- NI and tax question

Hi all, I work for a UK company and have a UK PAYE employment contract. My firm have allowed me to move to Spain permanently and continue working remotely from Spain. My company will not use an EOR or register in Spain for paying my social security to Spain. Nor will they allow me to become a contractor. My question is what should we do once my A1 form expires in November 2026. Is there another form I can use which will make this a permanent arrangement. I am hoping that the double tax and social security treaty between the UK and Spain will allow me to just continue to pay into the UK and not have to pay in Spain, which the exception of perhaps some additional income tax as a tax resident in Spain. Any suggestions? Thank you Luke

Hi luke27586,
If you are permanently resident in Spain, and carrying out your employment in Spain, then you will be liable to Spanish social security.
You will be no longer liable to the UK.
Your employer  should contact the authorities in Spain to enquire about what tax and Social security will need to be paid.
Thank you. 

Hi Luke27586, Did you get any further with how to resolve this? I'm intending to move to Spain next year with my employers consent but am likely to end up in the exact same position after the 2 years and the A1 has expired. I doubt my employer would register as company in Spain nor allow me become a contractor. (and giving up 16 years of permanent employment with them).