Ummm could be as soon as week 3. I don’t know why you’re wanting to risk it if you’re gonna cut it down anyway? Or are you waiting to harvest pollen? If so I’d just move it to a different area or outside for a few days..
Once you have sacs like that, you can kill it off and they will open as the plant dies and release that pollen too.
This is all assuming you’re trying to harvest pollen. If not, I’d kill it off asap