Just an update chaps - HMRC relented today and gave me the full FRE (£850) plus as an additional new year's freebie... If your military pension is correctly taxed at source (40%) and your current employement is PAYE then you can ask that they stop sending you a tax return
Which should save you all around £120 on accountants fees.
Thanks to all for your suggestions and support.
If you haven't applied for the FRE yet then why not????