Ok I will first try and describe my situation. Was selected for promotion leading rate in March 2011 just days prior to deployment on H14. The promotion was to take place on 31st march as long as I had completed career course and leadership. Upon return from deployment was told I could not get a career course until April 12. Completed career course and leadership March 2013 with promotion and pay backdated until 31st March 2012. This was shown in my pay April 2013. Now the amount of backpay was over £5,000 and as I am now a higher band level 2 leading hand this is going to push me in to the 40% tax bracket for any LSA and other payments I receive this year. Despite the backpay having been earned the year previous where I was a lower band AB on level 7 and received no LSA as I was on course. Can I contact the tax man and have this taken in to account as it seems wrong that money I earned last year is going to see me off this year. Or have i just dipped out and need to take it on the chin? Hopefully I have made this as clear as I can and thanks in advance for any help.