So I lost two old mega-torches that covered my whole island with like 10 blocks that have regular torches. However one day passed and two of them disappeared. Odd thing is that I wanted a mob farm back up again so I assumed that two old mega-torch were gone for good and it's been 3 minecraft night and no mob has been spawned.
Now I'm thinking that two old torches didn't break but rather invisible or some sort and their effects still lingers. I don't know if I should do a full sweep of breaking blocks of their last known cords.
let me know on slack when you log on and I'll see if I can find/remove them!