Variability in total flux of the nine observations of NGC 1566 taken between August and September 2025, for the 300V grism (left) and the 300I grism + OG590 filter (right). Top panels: Spectra in 10⁻¹⁶ erg s⁻¹ cm⁻² Å⁻¹, color-coded by observing date. Bottom panels: Evolution of the flux, integrated over different bands, as a function of the modified Julian date (MJD). The average flux is indicated with a dashed line in each bottom panel.