Double Taxation re lump sum payments for non-UK resident living in Canada

I am trying to get answers re whether I can claim back tax paid on a lump sum AVC pay out but can’t get the answers I need. I immigrated to Canada 2009. I have a UK Civil Service AVC which I am taking out as a lump sum this year. Legal and General will be deducting tax on this. Can I claim this back? It is impossible to get help from HMRC “helpline”. Tried Facebook, no good either. Their notes aren’t very helpful or clear.

Hi,

You will need to complete a Canadian double taxation claim form that you can find here:

Application to claim relief from UK Income Tax and claim to repayment of UK Income Tax

Thank you.