looks like it is already drawing from the leaves... i'd skip the flush...
don't fall prey to that nonsensical groupthink from which every reason given is bogus until they make up new reasons they never mentioned before....
trichomes on calyxes only
pistils - coloration, retracting etc..
density of buds...
3 observations you can make to guide your harvest timing...
looks like some long white pistils all over still and in fairly good supply. i'd wager you ahve 2-3 weeks left, but they can always surprise you with fast end development, too.
anyway, pay attention to all three.. get familiar andyou'll more consistently know when to "flush" if you choose to and more consistently choose teh same point in harvest window -- this is a good thing. you can learn what you prefer instead of relying on what some hams write on the internet. try early, try middle, try late... figure it out... it may take a little trial and error, but even a slightly different harvest day will still produce good pot.