It has been like this since we moved in 11 years ago. I have looked at it a couple of times and given up as it was not at all obvious how to sort it. There are 4 lights in the hallway, wall mounted uplighters. These were all removed recently to allow for replastering, the wiring all looked fine...
Hall lights, will switch on from end A and off from B - but will not switch on from B if switch A is off. First 2 pics single gang switch B 2nd 2 pics three gang switch A
Switch B (Crabtree) has 2 cables servicing it - a 3 core and earth - Yellow, Blue and Red + Bare earth and a 2 core...