Provided you have been non-resident for at least a complete tax year previously (19/20) you can take what is called split-year treatment for 20/21 where you will be officially classed as UK resident for that tax year but will in fact be treated as non-resident for the portion of the year up to when you return. To avoid complications it is best to make sure you receive all you outstanding payments before you return so that it is received in the non-resident part of the tax year.
See this HMRC document for all the details:
https://www.gov.uk/government/public...dence-test-srt