Direct sun light wont bleach a leaf like that unless the plant has been under artificial light. If you just took that plant from indoors to outdoors, and didn't harden it off first, it's sun bleaching. Otherwise, cannabis plants don't get "sun bleached" leaves under normal circumstances. Did you spray neem during the day? Another photosensitive foliar product? That is what it looks like to me, because the bleaching is occurring where the spray would pool up.
I am curious of the cause myself.