[O/Fe] versus sSFR relationship for galaxies. The location of M4327 is reported alongside a literature sample comprised of nearby dwarf galaxies, local galaxies with blue supergiant-based metallicity estimates, extremely metal-poor dwarf galaxies, and high-redshift star-forming galaxies/stacks, as presented in Chruślińska et al. (2024) (see the legend, and references therein). M4327 represents, together with the Sunburst Arc, the only high-z galaxy with Te-based determination of both gas-phase oxygen and Fe abundances (the latter corrected to total Fe/O abundance as detailed in Sect. 4.3.3). The hatched bar indicates the average abundance ratio of the MW thick disc and/or halo dwarf stars with [Fe/H] < −2 from Amarsi et al. (2019), whereas hatched symbols mark high-z galaxies with indirect determination of stellar metallicity (Fe/H) via modeling of optical lines. Shaded areas represent the model [O/Fe]–sSFR relation derived as detailed in Chruślińska et al. (2024) (see their Eq. 1) for different assumptions on the SN Ia delay-time distribution, namely a power-law DTD with slope equal to −1.1 with τ_Ia, min = 400 Myr (blue) and 40 Myr (green); upper and/or lower curves of the same color correspond to different choices of the relative iron yield of SN Ia and CCSN, namely C_Ia/CC = 0.74 and 2.5, respectively. The brown, dashed line marks the same relationship as obtained in TNG100 simulations with f_Ia ∝ −1.12 and C_Ia/CC = 2.04.