Lower panel: Specific entropy of model 001-1 at two different moments of the evolution. The red line corresponds to the peak of the He flash, meanwhile the blue dashed line corresponds to the onset of the PIE. The red- and blue-shaded areas are the convective zones at each of these stages. The gray shaded area corresponds to the H-rich envelope. Upper panel: Specific entropy of model 001-7, which does not experience a PIE. Here the blue dashed line corresponds to the moment of the evolution where the convective zone reaches its maximum extension.