Evolutionary tracks showing the longitude of upwellings (red) and downwellings (blue) as a function of time for the models with different surface temperature contrasts. The nightside is indicated in grey. If the nightside temperature remains low enough for the surface not to be fully molten, a strong upwelling preferentially occurs on the dayside (A,B). If the nightside is fully molten, upwellings form at different locations around the CMB, and some will also move towards the nightside (C).