Same as Fig. 8 for f₁ (left) and f₂ (right) for one-season runs. Panels 1A, 1B, 2A, and 2B are obtained using only the data up to 2007.0, so that we can directly compare the current results (blue and red lines) with those obtained by SSJ07 (green lines shifted by −20 and −5 s in panels 1A and 2A and 1B and 2B, respectively). The small horizontal shifts of the first and last points are due to the addition of three observing runs that were not present in SSJ07. Panels 1B and 2B show that in the current results, the period of the sinusoid is slightly shorter for f₁ but longer for f₂, so that at the end the agreement between f₁ and f₂ is worse with respect to SSJ07. The reasons of these differences are discussed in the text. When we add the new data, the longer period of the sinusoidal component of f₂ with respect to f₁ is confirmed (panels 3B and 4B), and moreover, we note a further difference in amplitude. Panel 3A confirms the change of regime of f₁ near 2009 that was already visible in Figs. 7 and 8. This change also tends to worsen the fit of f₂ (4A), and for this reason, the fits shown in panels 3A to 4B are obtained considering only the data up to 2009.0. Panels 5A and 5B show an alternative solution obtained using a low-frequency sine wave for the long-term component of f₁, as in the lower panels of Fig. 8. The fits shown in panels 5A to 6B were obtained using all the available data. More comments are given in the text.