An Accurate 8 can be far from what the name suggests. Mine never worked at all.
Run off tests are not accurate either apparently.
Ive bought a Blue Labs soil metre as my last hope in monitoring soil PH. If Im honest, after trying everything on the market I dont have a lot of confidence it will work properly.
Seems to me no one really has a handle on PH in soil.
Its some kind of dark art that can never be mastered.
Watching a few of the top growers around I notice they rarely have PH problems.
Experience has taught them to choose the right soil to start with and they never look back.
Very best with what ever works for you!

Just my 2 cents.