We analyze how the magnetic disorder affects the properties of the two-band $s_pm$ and $s_{++}$ models, which are subject of hot discussions regarding iron-based superconductors and other multiband systems like MgB$_2$. We show that there are several cases when the transition temperature $T_c$ is not fully suppressed by magnetic impurities in contrast to the Abrikosov-Gorkov theory, but a saturation of $T_c$ takes place in the regime of strong disorder. These cases are: (1) the purely interband impurity scattering, (2) the unitary scattering limit. We show that in the former case the $s_pm$ gap is preserved, while the $s_{++}$ state transforms into the $s_pm$ state with increasing magnetic disorder. For the case (2), the gap structure remains intact.
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