Pauldes

On drawing my NHS pension I received a cash free lump sum which was equivalent to three years pension. This equated to approximately 13.7%. of the pension value and was deemed to use approx 31% of my IP14 protected pot. Can I use any of the unused cash allowance from the NHS pension to give a larger tax free sum from the Sipp. My Sipp administrator says that the calculation is based only on the remaining % of the protected pot and will not take into account that I only received 13.7% cash from my NHS pension. Am I right in assuming that a "transitional tax free certificate" would not be of any benefit as these are two separate pension pots?