Hey dude, personally I'm not sure about topping. Tried a few, not overly impressed, but probably did it at the wrong time! I'm just not totally convinced it's necessary if you have plenty of light and leaf tuck? Or if height is an issue, I have supercropped a couple.
With the big mephistos I've grown under cobs, leaf tucking resulted in multi-cola'd plants with a slightly dominant/larger main cola, but lots of big secondary colas. And the ones I've supercropped have also distributed the old hormones around pretty evenly without topping. I don't think I've had any plants with one massive bud on one main cola to be honest, they've all been big multi-cola'd, which makes me think why top??
Still just not totally convinced that topping offers any real benefit mate? What you reckon? I know a lot of people do top autos, I'm just not a fan