Pre - flowers 🤷‍♂️

An auto flower can start showing signs of hairs or pistols in just 2-3 weeks, this doesn’t mean it is no longer in veg and start your nutrient cycle on flower. Unlike the photoperiod, the auto will rapidly grow and go into flower at the same time, usually taking about 5-6 weeks to go into full flower cycle, when buds start to form. Your feeding schedule should not be the same as a photo.

Ja ist normal,Autos blühen unterschiedlich,manche in wenigen Wochen andere brauch ein paar Wochen mehr,auch gibt es Unterschiede bei der gleichen Sorte. Alles gut und viel Erfolg

It's no different than a photoperiod except for the 1 trait of 'automatically' going into flower without a long dark cycle. So, if you see preflowers, it's probably been in flower for 7-10 days or more depending on how developed they are, which these look closer to 10 days than 7. Treat it as you would any marijuana plant 1-week into flower. A lot of the rhetoric about autoflowers is misguided or plain wrong. they are just plants. nothing magical about them. MAybe, with such a short, forced vege phase, they are less robust to poor feeding procedures? More likely, people should treat their photoperiods like their autoflowers in that regard, lol.

don't listen to deepsheeba allmix has plenty for 1-1.5 month

It's already in preflowering stage. Expect a more robust development. Rise the EC of your solution if you don't have enough space over your plants. An higher ec will limit the amount of stretching of your plant