I don't know about the pH, you've got a lot of chemistry going in your pool and pH is difficult to predict. But, we do know how to measure it and how to adjust it. As you're near the bottom of your pH scale, you need to raise the pH with Borax. Half a box slowly in the skimmer with the pump running, let it mix a couple hours and measure it again. As you'll be dosing with dichlor, we can guess the pH will drop as the chlorine is consumed so let's aim for a relatively high pH - 7.6-7.8. Another reason for somewhat higher pH while getting rid of amonia is that the intermediate CCs may be less noxious at higher pH. But do try to keep it in range.