We discuss a potential MeerKAT campaign to shed more light into the nature of the optically identified Blue Early Type galaxies (BETGs), a subset of the so-called "green valley" population, quenching star formation on time scales of less than 0.25 Gyr and the likely progenitor population of post-starburst galaxies. Employing a WSRT pilot survey of four galaxies, we have shown that BETGs have radio properties that fit to a mechanical removal of star forming material, potentially by AGN activity, as in particular we found H I to be removed farther and farther from the centre of the galaxies with older and older age of the stellar population. We argue that MeerKAT is the optimal instrument to conduct a pointed survey of BETGs to become more conclusive about this specific transition state, which is so rare that it will not be detected at a high enough rate in planned sufficiently sensitive large-sky surveys, for which we expect a total detection number of the order of 12 objects.