Further tests to determine the cause of the observed variability. Left: Fixing the obscurer parameters to their time-averaged values in Obs 1 (Table 3), and fitting N_pow (red circles) and N_comt (blue triangles) in each TB. Right: Fixing the continuum parameters to their time-averaged values and fitting N_H (magenta diamonds) and f_cov (orange triangles). In both scenarios the changes in the parameters suggest that they could contribute to the observed variability. See Sect. 5.3 for details. The uncertainties on N_pow (left) and N_H (right) are relatively small that they are within the data points. The photon index and reflection scaling parameters from the continuum show the same trends as Fig. 7 when the obscurer parameters are fixed. The ionisation parameter of the obscurer does not change when the continuum parameters are fixed.