Extrapolation to the very high energies of the spectrum of the EHBL object 1RXS J032521.8−56354 at z = 0.06, assuming an intrinsic power-law spectrum (dotted line) with intrinsic exponential cutoff energies at 10, 30, and 100 TeV (the three dotted lines, see text). The short-dashed lines are the corresponding EBL-absorbed spectra from FR2017. The CTA-south 50 h sensitivity is also shown in energy bins.