Early retirement
The earliest you can retire (under current legislation) is age 55 unless you are retiring on the grounds of incapacity.
Your pension will be reduced to allow for the fact that you will be receiving it for longer. The rate of reduction applied to your pension is decided by the Trustees, once they have considered the advice provided by the Scheme Actuary.
Please note: the minimum retirement age will be increasing to 57 from 2028.