Evolution of the critical rotation rate, j_crit, depending on the dissociation using two methods. This critical rotation corresponds to the apparition of the mixed modes. The higher the dissociation, the later the transition. For the blue points, we used the discontinuity end of the dominant m at χ ∼ 4. For the magenta points, we used the advection timescale, τ_adv, from the shock to the gain radius for m = 4 and χ ∼ 4.