@daz450 I hate to tell you, but I eventually installed ATV 6.4 that has the all the LED controls and I hate to tell you this but it either turns on/off the diagonal light. ........ so I guess before you are just lucky that the ATV6.3 image you had installed left teh light on.
Most users want the ability especially at night to turn the Led lights off - and now you can turn off both Leds if you want to do that