Do the turrets stay true on second focal plane? — 4 Answers

yes but the reticle is only true on max power

On second focal plane scopes, reticle is only true at one specific power setting

On a second focal plane scope the turrets, and the sub tensions of the reticle on both planes are only accurate at 1 magnification level, generally it's the highest magnification level of the scope, but not always. You could set up and zero a second focal plane scope at halfway through the magnification range say on 6 power for a 3 through 14 power scope, and everything would be accurate at 6 power but would be off one direction for a lesser power and off the other direction for a higher magnification level.