Yes, that’s how it works in Abaqus and CalculiX. Non-perturbation steps use the state of the model from their predecessors. It’s visible when plasticity is involved. The OP parameter is just to control the boundary conditions, loads and other step-dependent features. When set to NEW (always in PrePoMax), all those features that are supposed to be still working have to be redefined in each step. The remaining ones are removed. When set to MOD, they are carried over automatically and there’s no need to respecify them. You can modify them or add new ones though. But this parameter doesn’t affect the material state.