It depends on a lot of variables such as how long does the auto take to start flowering? I ran expirement giving my autos high nitrogen fertilizer to try and delay budding and I believe it worked ( didnt think of leaving a control) and I dont think it affected the yeild either so you can try giving them extra nitrogen but you could fuck em up, most people say dont use much ferts but as far as I'm cconcerned if you crank it up slowly they'll handle it, besides all that I never tppped mine except a diesel ryder whos top I broke while it was a week or two into flower it still budded just fine but instead of an 8-12 g top I had two 3.5ish tops I dont think it'l hurt em a bunch but it may not do much good either, ultimately I'd also look at how big the space is and will an untopped plant shade the shorter busher ones, in a four by four with 10+ plants what you'll lose from the auto shadeing the rest wouldn't be worth leaving it be, in that case I'd top and call it a day, also if the space is small you could end up with a 3-4 auto and a bunch of two foot bushs and have to raise your light to say 4 foot six inches and waste all that light intensity that would be better spent being closer to the photoperiod babys