1. Calculate the original maturity amount.
2. Calculate the surrender value of FD (principal amount + interest till now - penalty of breaking of FD(it will be 1 or 2% of interest earned))
3. Calculate the new maturity value with the remaining tenure, current interest rate, and new principal amount (i.e. surrender value from point 2)
4. Compare the old and new maturity value, if it makes a difference then you can create new FD, otherwise continue with the old FD
Also, you can create FD laddering to deal with this increasing interest rates