Joetom,
...they will offer all staff the choice to accept this 18.75% pensionable pay rise...
They may do, although I doubt it. Either way, you would still have to pay for it yourself - same as we are.
Out of interest, and not trying to start an argument, what percentage of your basic pay is your pensionable? Prior to the new agreement, ours was 80%. Now it is 95%.