you can top but i warn you with some autos they do not like topping, i would tie her down and do lst on her since she is an auto, you want to open her up to get light exposure to those lower areas.
you will really like that way of training. she will harvest a lot for you
No, do not Top it. Autos should be TOPed befroe the 5th pair of true leaves fully open, why? because after that the plant start flowering, and at that point the plant should not be topped.