Correlation between the BAT count rate and the PCA count rate for four episodes during the outburst. The solid points are from MJD 54796–54815 (the hard state as diamonds and the hard-intermediate state as squares) with the BAT rates shifted forward by 8.5 days. The open points are from MJD 54815–54859 (the soft-intermediate state as squares and thermal state as diamonds) with the BAT rates shifted backward by 1.0 day.