Polarized flux density |𝒫| correlations between 229 GHz (HI band) and 213 GHz (B1 band) frequencies (blue curves). Locations of the correlation maxima with associated uncertainties are indicated by blue shaded regions. For 2017 Apr 6 and 7, no significant delay has been detected. On 2017 Apr 11, the B1 band lags behind the HI band by 45 ± 15 s. The result is consistent if only the first 2 h of the Apr 11 observations are used (i.e., before 11.0 UT, corresponding to the loopy period, red curve). The lag disappears if only the latter part of the observations is analyzed (after 11.0 UT, orange curve).