I wouldn't leave her till 40% amber. You'll risk getting nanners from overripening her. (overripe stress) 5 to 10 % will usually sufice before you reach the risk factor. Nanners at this stage are painful, as the nanners can form inside the buds. This means you might end up with buds full of those little tiny seeds that explode when you light 'em, and it only takes a few days for the seeds to form enough to explode. (they keep maturing after harvest, till too dry to continue )

I like starting them with fresh soil surrounding the rootball, after the root trim. Less problems down the line, than just leaving them in the same container they were flowered in.

If you only trim some of the buds, when you re-veg...those 'buds' that are left will do three major things.
First...I believe the flowering hormones present in the buddage delays the process of reverting back to a vegetative state. (delays fresh, vegetative growth)
Second...as it starts to re-veg, the bud structure itself, morphs into a provider of fresh shoots. It's no longer a 'bud'.
Third...although the old buds may have been there to begin with, after a month of reveg, it has stretched-out to resemble a fat, hairy, leafy stem with mature/overmature trichomes that will really stink the place up.

Moral: Try both ways, and see which you think is better, but until I can find a better technique...I'll continue to pluck all of the buds prior to putting her back into veg.

Doubtful I need to tell ya good luck, as it's really not that difficult. :jointsmile: (but good luck :thumbsup