My gauge is when it starts being reliably at or above 50 at night.
Good luck to your Sans! Not that I wouldn't welcome a pic &/or offering my opinion of it here, but wouldn't want you to miss-out on possible advice that might be offered by someone who didn't visit this discussion. If you want to ask 'the world' why it might be doing poorly, you could start a discussion about it.
Hope is never dead, hopefully!
