Typical time delays obtained from the SSC flare model (shaded area) and expected from a linear LIV effect with an energy scale at the Planck energy (full lines) with the redshift evolution found in Jacob & Piran (2008). Other formalism such as DSR would lead to different values but of the same order of magnitude. The dashed line corresponds to Δt = 0. Positive and increasing LIV delays correspond to subluminal LIV effects, negative and decreasing ones to superluminal LIV effects.