I have heard a nasty rumour that if you have served for 10 years and over in one complete go ie no postings back to the UK. Then you are able to collect some tax back of off the tax man. Is this true or a complete load of ARRSE!!!
Why not 'ring' your local tax office (found on your yearly tax slip) and ask? You'll get it from the horses mouth, and you don't have to give your name or details. Link below with give you the phone number of your local office:
I've rang them on numerous occasions as I'm self employed, and my tax and NI are classed as 'big pain in rectum', and my local office is excellent at telling me 'no, we don't owe you any tax, you owe us', so be warned, they will look at your tax affairs for the ten years (married/single/divorced), time out of country, etc, blah. You may get lucky, or you may end up coughing up more !!