Flower formation

it takes some time to start flowering some strains will do it before some later. this is all because during the night the plants starts to make a light sensitive hormone and with 12/12 light being longer nights this starts to accumulate slowly and triggers flowering. i personally give my plants 2-4 days of full dark before switching to 12/12 this allows the plant to make this hormone undisturbed by light thus reducing the "stretch period".

Because that is when she really starts to flower. Look at this article from the grow weed easy website to see all the different phases from the flowering period so you know what to expect. https://www.growweedeasy.com/what-are-the-first-signs-of-the-cannabis-flowering-stage

I agree with my growmie, m0use...

When plants enter flowering stage they tend to go thorough a stretch first then start to make buds, its not instant flowers. Given your previous week photos of the plant I'd say its almost done/slowing down on stretching. It will be focusing on making more buds now, no more defoliation keep its feed and water schedule up. FYI: We will not be notified of any reply or tag [@] in the questions part of the website, if you need to reach out with other information use your DM "direct mailbox" in the bottom right hand corner of the page. it looks like a little paper airplane icon. Good Luck!