Simple sketch of the scenario we propose to explain the nonphysically fast change in position angle that is retrieved with simple companion-only fits. Our simulations show that for a close-in companion (solid circles), the best-fit angular separation derived with SAM interferometry (hollow circle) can be over estimated, if the companion is roughly aligned with asymmetric disc emission (red dashed region). The strength of this over estimation is related to several parameters, in particular the disc radius and the difference between the companion candidate position angle and disc position angle. An unfavourable alignment between the companion and the peak of the disc rim emission or a too small separation result in no overestimation effect in the derived separation and the companion candidate remains undetected. This seems to be the case at the 2013.8 epoch, where the absence of extended disc emission along the same position angle causes no overestimation. Here, the orbit of the companion candidate and the arc of the disc is misaligned to better represent the position angles found within the previous disc observations of the outer disc (~ 120°, green ring) and the position angle of the disc rim from the L′-band observationspresented here (~95°, black ring).