pEW measurements of Hα and He I for the comparison sample (SEDM plus newly classified SNe) overlaid on the density contours of SNe II (red) and IIb (blue) obtained in Section 4.2.1 (same as Figure 9), for three time intervals: 0–10 days (left), 10–20 days (middle) and 0–40 days (right). The comparison sample is represented by SNe II as filled purple dots and SNe IIb as filled green triangles. Dark green circles correspond to SNe initially classified as type II but exhibiting SNe IIb-like properties. Open purple triangles represent SNe, which were initially classified as type IIb but spectroscopically belong to the SN II class. Pink squares denote SNe II showing 87A-like characteristics. Yellow stars highlight SNe II that appear to exhibit SNe IIb characteristics but lack sufficient data to confirm this classification.