If you are working in the company, this would be considered as a transfer of personal data (Transfers of personal data to third countries or international organizations) falling under Chapter V in UK GDPR. So there should be a legal basis to be used. In your case, it depends on where your employment contract is. If your employment contract is in the UK but you reside outside the UK, that is not a problem. If your employment contract is outside the UK, but not in EEA, then there should be a transfer mechanism in place, like standard contractual clauses or binding corporate rules that should be signed between the UK company and your employer.
Please find more links here (references are for EU GDPR, but the text is the same):