Evolutionary tracks during the post-AGB phase (black lines) in the e − log P plane including the interaction with a circumbinary disc as described by Eqs. (7) and (9) (see also Fig. 1) with the adopted circumbinary-disc properties of Table 1. The  ⋄  symbols are observed post-AGB systems. The blue dashed lines show the final eccentricity corresponding to eccentricity-pumping as given by Eq. (9), modulated by the labelled values (1 corresponds to the adopted parameters). The timescale needed to pump the eccentricity can be estimated from Eq. (12).