It needs roughly 2-3 weeks. Don't trust what the breeders say, always estimate more time. You can chop it now but potency will be low and the amount of weed not the one you should get.
Breeders have optimal grow environments and also their finishing time is not the optimum time for harvest. They say 77 days in your case, which is the exact time when the buds begin to have trichomes which are crystal clear at this time. Theoretically you can harvest.
But plants don't count time in human days. They will be ready when the conditions on your grow room allow them to be ready. Very few have optimal grow conditions in their grow room's.
Also the criteria of a plant being ready are what? Basically when all the trichomes become milky/cloudy then it has reached maximum potency. Do a daily check with your microscope/jeweler's loop to see what is going on.
Read this to understand better
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I get it that you are very stressed and you need to smoke weed, but you have to be patient. You must also calculate a bit over a month for curing after you dry your buds to enjoy them at their full potential.