I'm not sure if I understood correctly. Do you mean running a new cable from the 2-gang switch to the new switch?Move the red which is now in com into L2 and run a 3 core and earth to the new switch.
Then connect in both switches
Brown to com
Black to L1
Grey to L2
Oversleeve the black and grey, brown.


Do you mean running a new cable from the 2-gang switch to the new switch?
If the new cable needs to be 3 core and needs to go to the existing switch, then it probably wouldn't make much difference.Which is more convenient, to run a cable from the existing switch to the new switch, or from the existing switch to the junction box?
This is the easiest way by far you don't need a junction box.Move the red which is now in com into L2 and run a 3 core and earth to the new switch.
Then connect in both switches
Brown to com
Black to L1
Grey to L2
Oversleeve the black and grey, brown.
Yes.I'm not sure if I understood correctly. Do you mean running a new cable from the 2-gang switch to the new switch?

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