This Lower Earnings Deduction is a common factor in most Final Salary schemes although most people don't realise it until they get down to the nitty gritty of reading the rules. Ask if you can have a copy of your company pension scheme rule book (all employees should be given one) where you will probably find a detailed explanation.
Also, if your normal retirement age is 65, most early retirees from pension schemes have a further deduction made (between 3%-5%) for each year they retire below normal pensionable age.
The other thing to remember is that if you're receiving redundancy pay any payment over �30,000 is subject to tax, although you can often avoid paying this extra tax by asking that the surplus over �30,000 is paid into into your pension scheme as an additional payment. However, it needs to be done after you have left the company, otherwise it is effectively additional extra pay and becomes taxable.