A previous published model (D. Gonzalez, D. Araujo, G. Aragon, R. Garcia, Appl. Phys. Lett., 71 (1997) 2477) allows us to predict the plastic relaxation in the saturation regime of epitaxial layers. This model is in agreement with the experimental residual strain for InxGa1-xAs/GaAs epilayers below 40% In-content. Above 40% In-content, the predicted values of residual strain become larger than the experimental one. This disagreement takes its origin in the change of growth mode that implies a transition from a 60 degrees misfit dislocation (MD) network to a Lomer MD one. An almost complete relaxation can be reached by a Lomer MD network, which is not possible with 60 degrees MD networks. The difference between both kinds of networks comes from the repulsive interaction of 60 degrees MD that inhibits the lattice relaxation.