Pistols not turning Orange

Unfortunately, this plant is not heading into its final week of flowering, despite what the packet says! As long as she is still pushing out new white pistils, she is in active flower growth and has not started the final ripening process yet. Wait until there are about 95% brown/orange pistils before starting a 2 week "flush"/nutrient witholding period and harvest when there are about 98-99% brown pistils. This will give you well matured flowers with peak THC levels and a full experience.

I see you are going in a 80x80 growtent. Maybe take a look at your setup. Perhaps the intake air is colder and is affecting the plants closest to it. Maybe your humidifier is more focused on one side. Make sure there is no stagnated air. ...If it is not either one of those things, keep in mind what @ernesttwwg said.

Never take advice from a stoner

Seeds have different genetics, even when they are seeds from the same cultivar. DNA and DNA sequences get shuffled up a bunch of different ways, hence a bunch of different phenotypes from the same cultivar (strain). This is why genetics labs and smart breeders always backcross multiple times before bringing their seeds to market. Anyway, back on topic. Your plant is doing this due to genetics. Some phenotypes are faster bloomers, some are a little slower, and some get the short end of the stick and take forever. I hope this helps. Happy harvest!

I would let her run until she's done (and I DIDN'T mean to rhyme but that was a bonus!). Some plants just need more time. If you can grab a jeweler's loupe or a microscope to zoom in close to the trichs, you can see what THEY are saying about the readiness to harvest... and I would look at your other plants as well... ideal is for them to all be milky (minimum) and 10-20% of them amber ... Good luck!