I think your latitude figures in this somewhat, too. If you are in the northern US, you have more hours of daylight and the plant will start flowering later. For instance, the most northern parts of the US have over 16 hours of daylight at the solstice. The southern most points will have less than 14 hours of daylight. The closer you get to the equator, the more the days get to 12/12. Some strains will flower with 13-14 hours of light, so early flowering indicas could start flowering earlier. However...
Your plant looks really sativa dominant. I would anticipate that it may be longer than 8-10 weeks after you see flowers. I am in the northern US and I cannot get sativas, like hazes to finish before it gets too cold. Do you know the strain?
I'm not sure what size pots you have them in, but expect them to get quite a bit bigger--you have basically 2 more months of vegetative growth. You may want to repot into something bigger.