One method (method B) used to calculate your final salary looks at your last 10 years salaries.
These are revalued using inflation, which often makes them worth more than you are currently earning!
When teachers have periods of pay freezes and below inflation pay rises this method often produces a better final salary pension calculation.
This spreadsheet will let you enter your last 10 year’s salary figures and to check what is going to happen over the next few months and years to your Final Salary Pension. If it is going to drop then you should seek advice on whether opting out would be appropriate.