if they dont stink you can leave them, I always chuck mine, but I dont have to worry about stable temps in my bators, you have to think of your bator first!
I left all of my infertile in until I removed the egg turner. Even then, one snuck past me and I removed it the next day lol.
My bator actually holds fairly stable. So I think on Tuesday I will crack the clears and see what happened.