Honeywell cm907 to drayton wiser hub r

Hi,
After some advice about installing a Drayton wiser hub r. I currently have a honeywell cm907 but I'm totally lost on the wiring. I've attached photos of the current wiring and the diagram provided by Drayton.
Current wiring is brown/live to A, black to B & grey not connected.
Thanks in advance

 

You need a permanent live and permanent neutral, along with a switch live. You could check if the grey is a neutral, and use this along with the brown (which would probably be permanent live). The black is switched.

 

You will need a permanent L&N to the drayton, and those two wires in your pic go to 1&3 on the Drayton , no links