I don't see 4 to 5 weeks left in your grow. The lighting makes it hard to distinguish the true color but they look done to me. Not knowing the genetics, saying, some plants just don't pump out and fill in the bud structure. Looking at the trichomes on some of the pics I'd think your at least 6+ weeks into flower. If your sugar leaves are also turning yellow and dying I would call the grow done. Another month of flower may ruin your final product. As for the yellowing, if it's not intentional through final flushing I see toxicity. Light burn, over feeding, or even mites. Mites can suck the health and color out of a grow fast. Causing dying leaves. I see some curl and tip burn, again lighting or toxicity. If they are as yellow as they look in natural light flush and cut asap.
