Orbital precession of the osculating Keplerian orbit of a 55 day circumbinary planet (outer, red) inclined by 30° with respect to a 10 day equal-mass binary (inner, black). The different panels show different epochs of the precessing period. These times are labelled and shown in panel f) where we draw the planet’s precessing orbital inclination with respect to the plane of the sky as a function of time. The grey band illustrates the range of sky inclinations for which the planet has a chance to transit. The overlap of the red line with the grey band corresponds to epochs of transitability.