Bright yellow variegated comfrey, but not sure if this is 'Bocking 14' , Officinale, or uplandicum species Comfrey! Help pls!!

Bright yellow variegated comfrey, but not sure if this is 'Bocking 14' , Officinale, or uplandicum species Comfrey! Help pls!!

Observation - Bright yellow variegated comfrey, but not sure if this is 'Bocking 14' , Officinale, or uplandicum species Comfrey! Help pls!! - UK and Ireland. Description: Im really confused, as to which Variegated Comfrey species I have, since I recently seen it flower, and is sterile-not producing seed! So does this mean that this is 'Bocking 14' Variegated?! Is it normal for variegated comfreys to be sterile of seed? Or

Im really confused, as to which Variegated Comfrey species I have, since I recently seen it flower, and is sterile-not producing seed! So does this mean that this is 'Bocking 14' Variegated?! Is it normal for variegated comfreys to be sterile of seed? Or is it actually a 'Bocking 14' Species?! Heres 4 pics of the Comfrey for ID! 2 showing the flower colour, 1 showing the actual leaf (Which is actually bright yellow/gold, not pale white!) and 1 showing the sterile seed head. Your help with definite ID pls, would be very appreciated! Thanks...