In reality, your plant will be ready to harvest when it is ready to harvest. Your plant has no idea about what is written on the packet it came in, which gives a general guide and not an exact "this will be ready on day 438 at 2 minutes past 4" type of arrangement. Plants are organic living beings that will do what they need to do in whatever time frame it takes. Harvest maturity has so many variables, such as, temps, light strength, container size, nutrition, growing techniques and methods, grower skill, etc, that no exact formula will ever be right. Like I said, the times are usually very optimistic and only intended as a rough guide. Besides, what other options do you have, other than being patient and waiting for her to be mature enough for harvest? I don't think there has ever been a plant that I have ever grown, doing exactly what it said on the packet. Your plant is an individual and not a mass produced "cookie cutter" robotic product. At this stage they look beautiful and all you can do is to keep giving your current care routine and soon enough, you will be rewarded with some tasty flowers that you grew with your own two hands, with total quality control. And that is what home cultivation is all about, doing it yourself and total quality control!
Hope this helps,..... Organoman.