They should stretch like crazy at the start of flower. If you’ve grown before and feel comfortable doing it, I would do some light training and bend them where they open up, expose the lower bud sites and flatten the canopy.
Autos are fickle and I don’t grow them. I just don’t like having a set time frame to veg your plant. But, I see plenty of growers who do incredible things with autos.
You certainly don’t want to stunt it but opening the plant up will def increase your yield and produce a lot less larfy loose buds that aren’t worth trimming.
Good luck. The plants look to be in good shape.