Orbital phase shift in LS I +61°303. Top: consecutive radio outbursts in LS I +61°303. Three outbursts are indicated: one before the maximum of the long-term modulation, one at the maximum, one towards the minimum. Centre: the radio light curves are folded with the orbital phase Φ(P₁). The outburst does not follow the orbital periodicity and shifts at different epochs to different orbital phases. Bottom: the same light curves are here folded with P_average, the periodicity of the radio outburst (Jaron & Massi 2013).