Changing any “deal” part way through the duration of the agreement is never good and just breeds distrust. I will be entitled to my pension at age 67 which was not part of the “deal”. A couple of years addition is bad enough but adding 20 years is not acceptable.
Adding years every so often is likely to be unpopular but more palatable in the long run.
As people live longer it only makes sense to work longer but it should not be forced it is much better to use the “carrot” rather than “stick”
The only person who got all his work done by Friday was Robinson Crusoe.
Anything i post over three lines long please assume it is an article lol.