Ummm could be as soon as week 3. I donāt know why youāre wanting to risk it if youāre gonna cut it down anyway? Or are you waiting to harvest pollen? If so Iād 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 youāre trying to harvest pollen. If not, Iād kill it off asap