Harvest point

At this stage, all growth stops and now is the time for trichome maturation to occur. You still need another 7-10 days roughly. Don't worry about the fading and wilting leaves, this is somewhat normal. I imagine this was caused by you switching to bloom nutrients as soon as the first pre-flowers appeared. In future, continue with grow nutrients until there are small tufts of pistils forming, cannabis still needs adequate nitrogen in early flower. The yellowing you are getting now is due to the plant cannabilizing the nitrogen from its older leaves to assist with flower growth/maturation. Giving your plant a dose of nitrogen fertilizer now will not fix anything, it is too late for that procedure to have any affect.

Which week of flower are you? looks like week 6 or something to me. I would remove the damaged fan leaves and keep going atleast 1 or 2 more weeks. The buds will grow bigger perfectly fine with just the small leaves at this stage of flowering. good luck bro 😊👏

Leaves can fade late in flower. They store nutrients and are being used. Did you back off feed? I wouldn’t harvest because the leaves look bad. You’re cutting them off anyway. Give those buds some time under the light. Disclaimer. If you used a loupe and the tricks are the right color. Than harvest.