It all depends on the high you're looking for! If you have mostly cloudy trichomes with a few clear than you will have more of an energetic high, if you're looking for more of a couch lock high than I'd aim to start the flush when the plant has 15% amber trichomes because you want to flush your plants for a whopping 14 days and the amber trichs will keep popping up while your doing so...
So by the time your ready to chop you should have about 20-25% amber trichomes mixed in with the cloudy...when checking the trichs I try to check the bud only as the sugar leaves will mature and amber up quicker than the bud itself.
In other words I would recommend you give your lady a bit more time to get that amber in there! π Hope this helps growmie! Happy growing!βοΈπ