I can’t understand what the problem is here. All you have to do is calculate your threshold and adjusted income figures, taking into account all sources of income and ensuring that you correctly account for whether pension contributions were made under a net pay arrangement, received relief at source, include adjustments for any defined benefit/cash balance pension input or salary sacrifice. Then simply make sure you put the correct figure on your tax return; remembering, of course, that it’s all down to you, not your employer or pension scheme, to declare it correctly. Simples.
“Why you should never retire”
On my 50th birthday, I will always remember, amongst the card or two I received was a letter from Saga’ who’d managed to find out my age through the wonder of the internet, and were pleased to tell me I now qualified to join my parents and go on holiday with them.