Frankie Wheeler

Hi, I am a British citizen and have been based in Spain for the past 9 years, I hold residency here in Spain and I have been on a Spanish contract paying tax here. I have just accepted a job for a UK company and I will be remaining a Spanish resident. Therefore, I have completed the P85 form to notify I will be out of the UK and receiving income overseas. the question I have and also my employer, is what information for my new UK employer need from me to be able to put me on a 'non-uk resident' work contract in the UK. I understand that I will be paying tax here in Spain and only here in Spain, however, what does my new UK employer need to include on the work contract so they don't deduct any tax from the company at source. Will I receive a new tax code once my p85 is reviewed? Sorry for the long message. Thank you in advance! Frank