I will try to see if I can run new cable from MCB.Yes that would be fine, it just so the connections are accessible. I'd still ru the new length of cable as high as possible so you don't need to worry when fixing the brackets for the cupboards or cooker hood.
I have attached a layout to verify with you if this is more practical approach.
If I am unable to run new cable from MCB to new location of switch in that I case I should be able to add surface box next to spur switch. terminate (RED) wire from MCB into surface box. Run new wire (GREEN) from surface box to cooker switch.
Here comes the second challenge, should I run new wire (ORANGE) inside trunk down to the socket below kithen worktop and behind cabinet? as I don't think chisel the wall horizontally from old switch to new switch and layout (bLUE) wire by again using some sort joint ( which we are strictly trying to avoid)
So to connect cooker switch to socket I will see if I can chisel and run through that way. Otherwise is it safe to run (ORange cable inside trunk? or it has to be inside the wall? ( I am verifying this for regulations to be sure ).
Thanks for you hep and valuable time.