I don't know about that, it strongly depends on strain. some plants CAN be at peak harvest week 8. especially when it's a strong indica. the only way to accurately tell if it is done is by using a jewelers loupe to look at trich. regardless if the plant has been in flower for 7 or 13 weeks, it all depends on the trichs. if you wait 10 weeks for a plant that was ripe at 8 weeks you can hermie it, and cause significant loss of THC levels as it breaks down into CBD.
I would still say your plant could keep going a bit longer from what I see in the pictures. alot of your pistils are receding but I still see some that havent. though your post was from several days ago, I'd say a week more from those pictures. a good tip is to drop the plants into 36- 48 hours of darkness right before chop. it will help kick that buds into overdrive producing more resin and more thc