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tokens: shape of the -band excess or to place meaningful constraints on the frequency of such events, as we are insensitive to many periods. Nonetheless, this opens up the possibility that some of the variations in the CoRoT and Spitzer light curves could be due to short-lived, and potentially recurring, hot spot emission or to stellar flares. We recall that the system’s average colours do not show a significant -band excess (Paper I, Sect. 4.5), implying a low-to-negligible average accretion rate consistent with the majority of the CFHT light curve. It is important to note that the raw CFHT light curves consist of short runs of 5 consecutive observations and these have been binned using a weighted average to give each data point seen in the figure. Hence, the three points indicating a -band excess are derived from 15 independent observations conducted in photometric conditions. 3.2. Spot model Young, low-mass stars tend to be heavily spotted (e.g. Donati et al. 2000 ) and can display photometric modulations not unlike the LAV-dominated parts of the CoRoT light curves. However, changes in such modulations from starspot evolution tend to occur smoothly on timescales of many days to weeks (e.g. Roettenbacher et al. 2013 ), rather than the sudden morphological changes we see at rHJD 4544 in the 2008 CoRoT light curve (when the LAVs appear) and at rHJDs 5910 and 5930 in the 2011/2012 CoRoT light curve (when the LAVs appear and disappear, respectively). Given that there are two stars in this system, both of which are likely spotted, an appealing solution could be constructive and destructive interference of starspot signals where different active regions have slightly different periods. This could arise due to either different stellar rotation periods (the system is young and not necessarily synchronised) or, even if the stars are synchronised, different latitudes (differential rotation) 4 . We therefore sought to understand how much of the large scale structure in the CoRoT and Spitzer OOE light curves could be attributed to the constructive and destructive interference of starspot signals. We set up a simple two-spot model following the formalism of Dorren (1987) . Due to the well known degeneracy of spot models we allow only two starspots and opt for a single spot on each star rather than two spots on one star 5 . Before modelling the data we need to: a) determine the flux contributions of each star in each band; b) determine the flux ratios between the spotted and unspotted stellar photospheres and c) mask variations that are clearly not due to spot modulation: a) the observed flux in each band is the sum of the stellar and dustcomponents. Our SED modelling indicated that the dustcontributes negligible flux in the CoRoT band but makes up asignificant fraction at 3.6 and 4.5 m. The stellar flux fractions are 0.62, 0.41 and 0.34 for the primary star in the CoRoT, Spitzer 3.6 and 4.5 m bands respectively, and 0.38, 0.25 and 0.21 in turn for the secondary.