12/12 to 18/6

Is it too late for me to switch from 12/12 to 18/6? My plant is 10 days old. I don't want to cause stress at all, so if I have to I will stay 12/12 if that means no stress.

edit: my grow is a 12/12 FS.

No your plant will be fine and happy to get longer days. Think about nature. Plants sprout in the spring. From the time they sprout until the summer equinox, each day is longer than the previous. You are not going to stress the plant by extending your daylight. At ten days I doubt it has started to flower so it won't even be reverting back to the growth stage. Everything should be gravy for you man.

Why did you start with 12/12? Cannabis has been revegged plenty of times, so you can actually have PERPETUAL HARVESTS by flowering, harvesting then revegging...so in short, your plant will go through a period of transition, about 1-2 weeks, and then resume her vegetative state...no worries

It should be fine at this stage. after the 2nd-3rd weeks is when the light cycle really matters. According to one article