Background-subtracted Swift/XRT spectra of Aql X-1 for obs 1 (left panel), 2a (middle-left panel), 2b (middle-right panel) and 3 (right panel) after deconvolution with the response matrix using, as a model, a power law of index 2. In each panel, we show the Swift/XRT spectra (in green) together with Suzaku broad-band spectra (in black and red) taken at similar epochs during outburst evolution. For obs 2b, we also show the NuSTAR simultaneous spectra (pink, light blue for FPMA/B, respectively). Based only on the comparison to broad-band spectra from previous outbursts, we identify obs 1 and 3 with hard states and obs 2a and 2b with soft states (see text).