When you purchase the book after October 1st 2016 you will receive a pdf file of chapters 9 and 10 with the calculations redone to reflect changes to the pension rates at September 20^th 2016. Similarly, when you purchase after 1^st October 2017 you will receive a pdf file of chapters 9 and 10 with the calculations redone to reflect changes to the pension rates at March 20^th 2017, and so on, each six months.