Hey!
Like the 8thchevron said.. thereās a study going around thatās actually quite interesting and has some pretty good facts from research and thereās basically no difference in the final product.
I personally havenāt tried it myself Iāve been flushing since I started growing. But I will be trying it myself soon.
To answer your question on when to start flushing.. roughly 10 days before harvest. When thereās about 80% cloudy and about 5-10% amber trichomes. That gives her time to reach a full cloudy and 20-30% amber. To me thatās a great combination.
Good luck and happy Growing.