Sup pal. So, generally I wouldn't give a window without seeing your trichomes with a loop.
But, just by looking your are in the final days imo. Once all your buds are rock hard, or no bounce left to them. They're done with fattening.
So, you say 8 weeks. So, generally it takes 8-10 weeks depending on the strain type. But, by looking just at yours.
I would go as far to say you can harvest in a few days.
So, drop your light % by 20-30% or higher your light. Just start giving water feeds. Any small NPK needed will be taken from reserves from the plants leaves which should look like small fade, naturally ripening your plant.
Although I can't give 100% days it'll be finished in. You're 100% way into ripening and that calls for lowering your light % or hours given
No flushing is required, just finish her off by water feeds, try not to get run off as you don't want to flush any nutrients out. If you do get run off, just add it back in. Or let the plant drink it up.
You're in the home stretch
If you need help processing tips for harvest feel free to DM me or anyones advice you find suits your thoughts.
Good