Temporal evolution of the main spectral parameters describing the continuum emission of IGR J17498−2921 observed with NICER, along with the iron line. The top panel shows the 0.5–10 keV light curve, and the second panel reports the unabsorbed 1–10 keV flux. The associated uncertainties are reported at a level of statistical confidence of 90 percent. Downward-pointing triangles represent 90 percent c.l. upper limits estimated when a parameter could not be properly constrained, while the star-shaped points represent fixed values for the parameters. The spectral parameters are reported in Tables B.2 and B.3. The yellow-shaded region indicates the time interval in which the phase jump occurs (see Sect. 3.3).