How long you think to harvest (autos)?

So these girls are 75 days from seed. NL autos in 60/40 coco under LED.
 
I don't know how people mark the beginning of flower with autos, but I maked it when I first saw the first clusters of pistils in the flower tops, which was about a week after the very first pistil showing in a node. By my count, they're 4 1/2 weeks along.... 5 1/2 if you count from the first pistil.
 
Anyways, the topmost buds seem a little further along than the bottom ones.. more than half the pistils have turned orange and receded on those, though they're still forming new ones. Not as many orange pistils down below- stil mostly white. I'm using the Radio Shack 60x - 100x led loupe to check trichs. Seems they're about half and half clear/cloudy with a few ambers here and there. I recently cut out N, and I'm just running PK nutes now. I want to flush for a week before harvest... I'm thinking of starting my flush the first weekend of Dec. (about a week and a half).  What do you guys think? Too early? Too late? My first grow and I've put a lot of work in. I don't want to blow it by missing the window. Thanks and happy Txgivin!
 

 

I know some of the tips look a little burnt, I'm hoping cutting the N will straighten it out.

 

 
Cool, thanks man... but it's only been flowering 5 or 6 weeks at the most.. do you think it'll degrade if I leave it for another couple? I don't wanna miss out on that final swell I hear so much about- plus alot of white pistils still underneath. Not to mention I haven't flushed yet.

 

 
Thanks mang.. another 2 weeks is about what I was thinking too, so I'm glad at least someone out there concurs.
I'm not dry or anything so there's really no rush. I want these girls ripe.

 

nice job on your first grow, i'm surprised at your patience, alot of new growers come up with a reason to yankem early, your right about waiting for them to swell up, I recently finished a NL auto grow and they swelled up enormously from week 8 to week 9, I ended up with 4 zips off that plant, not the greatest yield but not bad for an auto. good job and good luck!!!!!!

 

 
Thanks man.. Usually I'm not the most patient dude, but I'm pretty determined to do this right..financially I'm at a point where I had to either quit or start growing, and there's no way I'm quitting.    Do you have any pics or a journal of that NL grow? I've gone through a few when I could find em, and it always helps to see what more experienced growers are doing with similar plants. The seed vendor states these can go 90-100 days, and that seems about right because they took 4-5 weeks to sex it on out. Made a couple mistakes too, probably lucky they're not more stunted.