Help w House and Garden

Hi all,
I have tried to search to find answers to my question, unfortunately my search couldn't find my answer. So hopefully someone on here will have used the product line before and can give a helping hand. My question is, when using Bud XL the feed chart/nutrient calculator says to give them Bud XL in week 4 of flower. Now is this 4 weeks from when I flip my light cycle or is it 4 weeks from when the flowers start to show? Typically there is 1-2 weeks from when you switch lights to when the flowers appear. Any help is appreciated.

TIA,

week 4 of flowering,it should be after the fact that you have switched over your light cycle.But if somehow you get flowering beforehand just calculate how much time of flowering has occured before you switched your cycle.

So, if I'm understanding you correctly, it's 4 weeks from when I switch my light cycle, not 4 weeks from when buds start popping. Thanks!!