Detectability of differential rotation following the MCMC analysis for a number of modes n = 33 in the period-spacing pattern. Zones in the (α_rot, Γ) plane for which we were able to reject the null hypothesis with a level of confidence of 95% are coloured in blue, while zones for which the null hypothesis cannot be rejected are coloured in orange, and zones for which any fitting of an inertial dip is considered challenging (no convergence of our fits) are coloured in beige. The bin size is reduced towards α_rot = 1 to better see the regime of near solid-body rotation. Limits between rejection of H₀ and no-rejection or challenging detection are shown in full and dotted-dashed lines for respectively n = 21 and n = 50 modes. For these numbers of modes, limits in regimes for which |α_rot − 1|< 0.01 are not shown for clarity.