The TFGM statement quoted, mentions State Retirement Age for concessionary travel, so 66?
60 year olds do not (to the best of my knowledge) qualify for concessionary travel in GM.
That is now definitely the current situation and the Concessionary Wayfarer is only for those at State Retirement Age, now 66.
Previously, until about 3 years ago it was available for anyone over the age of 60. I remember using the concessionary version 4 years ago, shortly after my 60th birthday, but it was very soon raised to state retirement age after that resulting in me not being able to use it again. Incidentally the price was much lower then at around £6. I also had quite a few problems getting bus drivers to accept it. I used one printed on rail ticket stock and because the price undercut their own day tickets they insisted it wasn’t valid and was just a rail ticket. I suppose a concessionary Wayfarer, looking like a rail ticket, was something that they didn’t see very often.
The Concessionary Derbyshire Wayfarer is still available for those aged 60 and over and is very good value at just £6.70.