Basically anybody that works part-time for a few years then goes full time and maybe gets promoted to a good finishing salary is going to miss the old final salary LGPS. It is mostly women affected by this.
Also anybody under 55 who was due to retire at 65 or earlier might now have to wait till 68 or even later.
The new average salary LGPS does have a slightly higher accrual rate i.e. you can pay in for less years, but the revaluation by CPI inflation rather than by wage inflation will hit pay outs.
Also anyone earning over 21k might have to pay in up to 50% more contributions. A massive increase. Remember this scheme is currently entirely self financing. Only on future projections of extended longevity of lifespans can these changes in any way be justified. These are predictions with limited accuracy.
For those on under 21k the changes don't seem so bad, as long as they aren't promoted and remain full time their whole career. But of course the deal for them was already terrible because a lot of poorly paid workers will die before they reach 65, let alone 68 or beyond.
Some unions are making a lot of the fact that what workers have already paid in to the LGPS will be paid out on the final salary terms and only new contributions are affected (except of course the retirement age which is critical change). But imagine how outrageous it would be if that were not the case.
Already people have paid into this scheme with a promise of retiring at 65 or earlier. They have been conned. They are not even being guaranteed 68, it might be much later. This is the key disgraceful change and until 65 is guaranteed this scheme is not to be trusted and members should vote to reject it.