There are few contacts with MPC formulation and few contacts with Augmented Lagrange. MPC is purely linear. But for Augmented Lagrange, Small sliding was turned OFF manually. This leads to a finite sliding and the Newton-Raphson iteration is triggered. For finite sliding the following is true (please refer to the following section in documentation: 3.9.7. Selecting a Sliding Behavior): “each contact detection point can interact with different target elements, depending on the contact status (open, closed, or sliding). The program re-forms nodal connectivity of the contact element based on the current configuration at each equilibrium iteration.” Therefore it will make a difference if you solve it in single substep or multiple substeps.