The threaded carrier was not coming off with a strap wrench, - including the rohloff one. I snapped a Boa strap wrench. In the end it took the attached tool by Park (what great tools) , a vice to hold the castellated Rohloff tool and two people to get the gates sprocket off.
I am very pleased to be back on the chain and a nice splined 16T sprocket. The bike is much quieter and smoother.