Comparison between the observed depletion pattern and the best-fitting model for a plateau-type profile (top, EP Lyr) and a saturated-type profile (bottom, CC Lyr). Observed abundances of elements are given as blue circles, while abundances from the accretion model are represented by orange squares. The elements used in the model correspond to those of Figs. 2 and 3. The model used in the top panel is a 0.55 M_⊙ post-AGB star starting accretion at 5000 K with M_⊙ yr⁻¹ and M_d = 10⁻³ M_⊙ (Fig. 9, green solid line in bottom panel), taken at 6200 K. Bottom panel: the model is a 0.40 M_⊙ post-RGB star starting accretion at 4000 K with Ṁ(0) = 5 × 10⁻⁸ M_⊙ yr⁻¹ and M_d = 10⁻² M_⊙ (Fig. 8, orange dotted line in bottom panel), taken at 6250 K. The initial metallicity of the models is normalised to the observed S and Zn abundances of both stars.