Table B.1.

Observed flux, EW, and σ of the BLR component of the Hα and Hβ lines, as resulting from our 1st-phase modelling (Sect. 3). The physical quantities are in units of 10⁻¹⁵ erg s⁻¹ cm⁻², Å and km s⁻¹, respectively. The 2022/LR-B^† row reports the parameters for the broad Hα obtained from the re-modelling of the LR-B 2022 spectrum over the VHR-R wavelength range (i.e. 6250 − 6900 Å).

Year		EW		EW
2004/SDSS	-	-	-	-	-
2019/LR-B	37.1±0.2	22.2±0.4	62.6±0.2	42.0±0.7	3690±16
2022/LR-B	9.2±0.3	6.5±0.6	37.1±0.4	24±2	2110±30
2022/LR-B†	-	-	56.8±0.4	38±4	2460±30
2022/VHR-R	-	-	64.6±0.2	42.9±0.3	2694±17