Q: Are you taking a big risk at killing a plant if you transplant during first couple weeks of flower. If so do you know why?
Killing no, Stressing and hermaphrodite the plant, possible. Defiantly don't suggest transplanting in flower, that's why you transplant in vegetation stage into a 5 gallon or 3 gallon pot. If you are feeling confident and ballsy you can always go for it anyways.