[SII]-VO87 (upper) and [NII]-BPT (lower) plots created using best-fit line fluxes for each source (see the values in Table 3). The distributions of low-redshift galaxies from SDSS (MPA-JHU DR8 catalogue; Kauffmann et al. 2003b; Brinchmann et al. 2004) are shown as background points. Left-facing arrows represent 3σ upper limits on N2 and S2. We include the demarcation lines for the z ∼ 0 galaxies of Kewley et al. (2001, solid lines) and Kauffmann et al. (2003a, dashed line). We compare our results with values from z ∼ 5.5 − 7.0 galaxies observed with JWST/NIRSpec MSA as part of the JADES survey (Cameron et al. 2023; black symbols).