Drop of optical depth due to dust ejection by a hypothetical planet, derived for our best-fit model disc with the formalism of Bonsor et al. (2018). The solid contour (cyan) indicates an optical depth reduction of 50 per cent. Hatched areas bordered by coloured dotted lines represent regimes already probed or ruled out. These are informed by the detection limit of a radial velocity (RV) survey with HARPS (Lagrange et al. 2013, from their fig. 7), the approximate detection limit of the NIRCam planet search (Ygouf et al. 2023, from their fig. 7) (upper and lower violet lines correspond to a planet located on the disc minor and disc major axis, respectively), as well as the parameters of a hypothetical ring-shepherding planet that could have sculpted the inner edge of the planetesimal belt (Chiang et al. 2009) (planets to the right of the corresponding dotted line are ruled out as they would have deformed the belt). Also indicated are the potential planet parameters of object ‘S7’, revealed by the NIRCam planet search. We estimate that planets above the white dash–dotted line would have caused a discernible optical depth reduction.