As said above, when growing in organics (with organic soil and organic nutrients), trying to allow for pH drift is not necessary. The reason is that you have microscopic helpers in the soil that take care off that for you. For those of us who use synthetic nutrients, we have to monitor the pH and allow it to drift and then readjust as that is the best way to get the results as Hammy said.
If the nutrients that you are using say to set the pH at 6.2-6.5 then do that with organic adjusters if you can fine them and set to that. I have to assume that they are either assuming that you are using lime in your soil or have instructions to use lime. The lime is very helpful in the soil as it not only helps to balance the pH but it provides magnesium and calcium when it breaks down.
For synthetic nutrient/medium grows, the nutrients are absorbed better at different levels of pH, therefore we have to adjust the pH lower and allow it to drift to get the best results. But in organics, pH is not as important to the plants absorbing nutrients because the microbes actually "feed" the roots the nutrients that the plant needs. This is a symbiotic relationship. The microbes get the nutrients and deliver them to the plants and the plants excrete carbohydrates that the microbes eat. They feed each other. Because the microbes feed the plants, pH only needs to be at a place that is comfortable for the microbes to live in. That is the mid range between 6.0 and 7.0 You shouldn't have to adjust your water to 6.0 to bring the pH down. Just set it about 6.3 (if the Nectar instructions say to go with 6.3, but you can allow it to go between 6.3 and 6.5 and the soil/microbes will do the rest.