CYA and PH

I understand that when you add cyanuric acid it lowers PH. My question is by how much? I'm needing 10lbs of CYA to raise my level to 50 in my 25000 gallon pool. My PH upon opening is high at 8.0. I'm adding muriatic acid to lower that, but want to take the cyanuric acid into account as well.

Using the pool calculator: https://legacy.poolcalculator.com/index-classic.html shows you will lower pH by 0.89

Thanks. I was guessing around 1.0. I can aim for 7.3 to get to "normal"