Yes you're right. Not sure why I couldn't find it before when it was definitely there in the DBs. One could speculate that the "Energetic" James mentions is a different tank to the one in action on the first day of Cambrai, such that the original "Energetic" was a Supply tank but the name was re-used for a fighting tank. But I'd have only imagination to support that idea and no facts, and that's not very satisfactory. Until more evidence comes to light (there must be more personal diaries out there, surely) it's a mystery waiting to be solved.