Hey there your plant looks great
Personally I like to wait till about 50 to 60% of the hairs change across the whole plant at that time it's when I start to really look and see if the plant is done. I suggest useing something to check tricombs but only check the ones growing directly from buds not sugar leaves those will turn way early. I like to look for most of the tricombs to be mily white where you can't see thru them and then the rest half clear and half amber
You probably have about 1 week to 1o day maybe 14 days at the longest
Just remember to be prepared for drying and curring don't wait till harvest to think of your plan.
Drying and curring is very much an art I suggest getting mesh drying racks and to wet trim buds at harvest and put buds completely trimmed on mesh racks immediately it will help not getting rot or mold and when you leave the leaves when you dry the plant and you don't have the temp down low enough the leaves make the buds smell like old soggy