Just to chime in, been growing outside for many years. Have used BT every grow and used it up unto the week of harvest with zero effect on the final product. I spray at dusk as BT degrades in sunlight.
I have only grown her outdoors, 3 grows all consistent quality. Very large plant, had one get over 12ft on me. Not a heavy feeder and a easy grow all around.
So, did you catch any of the Sphere shows? I might go this weekend ;)