They look good and healthy, but I would say they have more than 4 weeks left. I've never seen a written rule about when to count a plant in actual flowering, but for safe measures I always deduct about 4 to 5 days off the calendar after I switch the light cycle to 12/12. I notice it takes about that long, even after flipping the lights, for my plants to start flowering. A good tip is to veg your plants on a 16/8 cycle instead of 18/6, 20/4, or 24/0. They show sex and mature faster with less light. Around about the 4th or 5th week of actual flowering, they normally pack on massive weight, at least for me. Past about week 6 or 7 my plants don't do too much growing, normally just ripening and getting ready at that point. But this all varies depending on strain. Something with lots of sativa genetics probably keeps on growing, they can take as long as 14 to 15 weeks of flowering before they're ready.
Hard to tell from pics, looks like 2-3 wks, get a loupe️ Sent from my iPhone using Tapatalk @ I love growing weed
Hi Hunter Neeed your help Found my plants had few thelse leaves today and I'm panicking I've uploaded pics Please help