Hmmm. Are you saying the neon was lit when the switch was off when you woke up?
This link still works: http://home.surewest.net/frcn/Coffee/Silvia/SilviaWorks.html and has the wiring diagram for a Silvia. If you follow it, you can diagnose where the current is flowing. If that makes no sense to you DO NOT poke around with a multimeter. It is 100% 240VAC inside a Silvia.
Just to point to one possibility - my Silvia came with a super dodgey main switch. I had the experience of the neon being on whenever the main switch was on.