Evolution of the synchroton peak frequency ν_s versus time throughout the MWL campaign. The peak frequencies are obtained by fitting a log-parabola to simultaneous Swift-XRT, Swift-UVOT and Swift-BAT observations. Blue square markers indicate fits that result in a p-value above 10⁻³. Data points in violet triangles correspond to a p-value between 10⁻³ and 10⁻⁴, and red diamond markers have a p-value lower than 10⁻⁴.