Noob needs help with most difficult part of grow IMO

Hello. This is my first grow. To me, the most difficult part has been determining when it's time to harvest. I have 2 plants under a 400W HPS. They are both the same strain, JointDoctor's Easy Ryder autoflower. Both are 24" tall...breeder specified a max height of 25". Breeder also said fully mature in 70-75 days from seed. I totally understand that those #s are for optimal conditions and I've read before that this strain always takes longer. They are on day 100 right now. I know these pics aren't the greatest but it was the best I could do.

The plant in the pictures has only a few hairs that have not turned red/amber on the entire plant. Most of the trichs look milky. Only a few amber ones are present near the top of the higher buds. I always hear one of the things to look for are swollen calyxes. I'm slightly confused as to what to look for there. Do you just want them all swollen or do you want them all to swell AND open up?

Anyway....what do you guys think....done, or not yet? I have incredible patience . I can wait longer if I have to. I just want good smoke.

Thanks in advance for your help!!!!!!!!!!

They look done to me. I'd chop them and read up on non-autoflower strains for the future. 100 days and you can grow about 90% of the strains out there.

(figures about 30 - 40 days of veg and 55 - 75 days of flower depending upon strain)

Your yield will be greater...the varieties to chose from will be much greater...and it's not really that much more work at all.

cut one, smoke it. the rest is easy. look ready to me and the time's about right.

I like the nice purple color, sweet. Anyway, they are okay to harvest now if you like the buzz.(you should try out a test bud) As long as you are starting to get some amber trichs, they are mature enough to harvest, although most like to let them go a little longer. Right now, the buzz should be more uplifting, and if you wait til more trichs turn amber, it'll change to more of a body buzz. The choice is your's, depending on what you like.

yep, take one off and give it a test smoke. Looks like it turned out well, nice purpleish color tone. congrats on your first grow!