Well the electrician didn’t cost me anything as while waiting I pulled the integrated fridge freezer out from fitted kitchen in case they needed to test that socket and there’s a little damp there. By the time the sparks turned up the circuit had stopped tripping so we assumed it must be that that is causing it. So no money on electrician but need to get builder to work out why it’s a little damp there. Fridge currently in middle of kitchen ☹️