Time lags τ_γ, ν derived from the DCF (upper panel) and the ICF (lower panel) plotted as a function of frequency ν. Positive time lags mean that the radio light curve follows the Fermi/LAT γ-ray light curve. To investigate the core shift, the time lags are fitted by ${\tau }_{\gamma ,\nu }={\tau }_{\gamma }+C{\nu }^{-\frac{1}{k_r}}$, where τ_γ is the time a newly ejected component needs to travel from the jet base to the γ-ray emitting region at speed μ and C is a constant. Using the calculated power law index k_r = 1.09, the best fits (solid dark blue lines) result in the de-projected location of the γ-ray emitting region of $2.6\mathrm{pc}\le d_{\gamma }=\frac{{\tau }_{\gamma }\mu }{sin\varphi }\le 20\mathrm{pc}$. For greater k_r the lower limit of the γ-ray region would shift upstream in the jet to d_γ, min ≤ 1 pc for k_r ≥ 1.88 (dashed-dotted red lines), d_γ, min ≤ 0.1 pc for k_r ≥ 2.23 (dotted light blue lines), and d_γ, min ≤ 0.01 pc for k_r ≥ 2.26 (dashed orange lines).