Left: γ-ray (AGILE and Fermi), X-ray (Swift/BAT and MAXI), and radio (RATAN, AMI-LA, and SMA) monitoring of the 2016 outburst episode. Right: The same monitoring campaign for the 2017 outburst. Hypersoft state occurs when the Swift/BAT 15–50 keV count rate is approximately 0 cts s⁻¹ cm⁻² , and radio flux is below 20 mJy. Usually, a prolonged (~10–30 days) hypersoft state occurs before outbursts, which can also exhibit brief (few days) flares in the radio and hard X-rays, as happened in both 2016 and 2017 outbursts. γ-ray emission is usually attributed to changes to/from the hypersoft state (during the onset, and/or during the hard X-ray/radio flare, and/or during the onset of the outburst). Dotted and dot-dashed lines denote Swift and NuSTAR pointings, respectively.