I was decorating, and removed a light switch from the wall but didnt remove any wires. When i was putting the switch back on, I caught the common with the screw and lost all lights upstairs. I reset the rcb put still no lights, except the hall. I realised at this point the downstairs lights were also out, but they are on a different loop. I've checked the bulbs and changed the switch but still no joy. Could it be both rcb's? Ive heard they are generally the last thing to go.