Top: PA variability obtained by Kiehlmann et al. (2016) adding the data of this work. As a criterion to solve the 180° multiplicity we minimized the difference between successive data points. Bottom: R-band and γ-ray variability. The dashed line indicates the γ ray associated with a new jet component reported by Jorstad et al. (2017) that produced a PA rotation, while the dotted line indicates a new jet component seen in VLBI images (Rani et al. 2018) that did not produce changes in PA.