@Shuggz pH is a funny thing. You had enough soil at the beginning that watering and feeding at 6.5 would have been fine, but the organics in the soil lessen over time and the more dominant Coco takes over. If you keep watering at the 6.5 I am of the opinion that your plants will begin to show both pH and nutrient defficiencies due to pH lockout.
Brother, this is your grow. You have the information to make an informed decision. I’m here to mentor you and your grow and if you want to experiment with your pH that is completely up to you.
There is much documentation both on this site and all over the internet about potted MJ plants and the relationship between pH and nutrient uptake.
Please feel free to research the subject more in depth.