How late into the Growing process can or should you use Mold protector?

I purchased a set of grow protectors but am not sure how late into the growing process I should use it without changing the taste.

You always apply Nutrients up to the last 2 weeks of bloom. this allow plant to use stored nutrients, which improves the taste. You would flush the plants at this point. Most fan leaves will yellow and die off signifying that they are done, and plant is mature. :smile:
Sorry for the wait. Peace

A fellow grower says:

My question is more about the mold protector to keep the large buds from getting mold. Since I spray on the plants.