cooker switch needs to be moved as having built in oven and hob but the 6mm cable is about 6 inches too short to reach the switch. it will only be supplying the oven so could you join 6mm cable with 60amp junction box or crimp the joints to extend the cable. Access cant be done from above
A registered electrician could join the cables using a cable joint likely the shrink sleeve type with crimps but I would not want to do this work because of the Part P charges for a non registered electrician are so high.
So just not economic to DIY this work unless LABC are going to be involved anyway.
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