Solar Orbiter/STIX spectral fitting of the earliest spectra for all events under investigation. The solid black line represents the observed background-subtracted flare spectra, and the dashed black lines show the background. The SOL2021-09-23 event (left) can be fitted with an isothermal component (red) and an additional nonthermal thick target model (blue). All other events, SOL2021-05-07 (middle-left), SOL2021-10-09 (middle-right), and SOL2022-03-11 (right), can be fitted with a purely isothermal model only. The resulting fitted parameters can be found in the legend.