And if there is some sort of arrangement to reduce their extra tax, will there also be one so that the lesser paid pay English tax not the reduced (for them) Scottish rate?
Which is why an LOA system would be flawed. You would have to give money to those earning above 33k and take money off the juniors set to pay less tax! The whole argument should start with uniformity and every serviceman/woman should pay the same rates of tax wherever they may find themselves posted or wherever they should choose to domicile themselves during their military careers. If a Scottish offset was demanded by 'wee Jimmy Shrek', then this could probably be achieved although as noted, the winners and losers may in fact balance out.