When pistols are new they are white, but as the age they begin to darken and the calyx around them swells.
It’s completely normal, and come harvest time- most of them will be this color. I wouldn’t read to hard into it. That being said- if it were the actual bud structure, and not just the pistols Id be a bit more concerned.
According to your diary your lights are 6 inches above? Keep your eye out for any bud bleaching or fox tailing. Raid the light up a few inches if you are noticing an more issues 🌱