Single LSD Grow

Solid week, working on dialing in automation system. I was out of town for the weekend and it was really cool to be able to check on pH/EC while I was away. New batch of nutrients with less mega crop and a little more Liquid Cool Bloom for PK. Fall weather means the humidity has dropped. I was seeing temps of 75 in the tent with humidity as low as 25%. After doing some digging, this is definitely not ideal in terms of VPD. In the short term I've been spritzing the leaves with some water once or twice a day to keep humidity around 40%. Seeing some brown tips from what looks like light burn. Sounds like this is expected if VPD goes too high, so hoping it will go away with higher humidity and/or lower temps. Not sure if I'm going to have to harvest part of the plant first - some stems have 5 petal leaves and almost no pistils left. No amber trichomes, but otherwise look almost ready. Two new branches have been growing quickly. These have 3 pointed leaves, lots of pistils, and the flowers are much less mature. Is it possible for a plant to have a genetic mutation only in some parts?