In the future, don't let the canopy deteriorate at such a fast rate... a downward trend may ensure that you are not overfeeding, but you still need products of photosynthesis to build molecules and replicate cells etc... THCa and terpenes are not exceptions to that rule. No reason to have a bunch of immature and 75% dead leaves before it finishes.
it's important to know the amount of photosynthesis that can take place in the top layers of the leaf drastically dwarves any other green surface on the plant -- unless you are growing a palo verde tree.
days flushing is irrelevant beyond the plant not dying too soon. Observe trichomes, ensure calyxes have fully fattened, and react to a certain percentage of amber trichomes... you need to jump off this ledge. people cannot jump off this ledge for you.