What am I looking for to tell if she’s entering flower?

Should be soon. Autos are stating to be just as long as photoperiods now a days with longer veg times. if your pressed for time auto will enter flower early from stressors like over feeding. Good Luck!

Look at the main stem where the branches grow/sprout from. When sexual differentation occurs, calyxes with white PISTILS ( also known as primordia/pre-flowers) will form here, 2-3 weeks before flowering commences in earnest. Week 7 in my diary "cannabis conundrums" has pictures of these primordia, if you are keen to see what to look for. Just remember, - less leaves = less energy production = less growth! Heavy defoliation can cause delays with flowering. Hope this helps, Organoman.

It will start producing pistils or will form balls if a male which there would be no pistils then.

Yours look like pistons are gonna pop within the next 3-7days. Very healthy. Good luck.

You will see calyxes start forming with white pistol sticking out