Energy flux observed with LHAASO extracted from publicly available data (Cao et al. 2023) for the periods reported with spectral index. In the analyzed time segments (named time bins: see Table 2) the light curve of LHAASO has been fit with a constant (pol-0) that represents the flux of GRB 221009A for that period. The blue markers in the top panel report the rebinned LHAASO flux for each period. The bottom panel reports the intrinsic spectral index observed with only LHAASO.