Different verifications are performed in all the obtained scans, which are flagged if anomalies are identified. For instance, Autoflag checks that the timing of the acquisitions is correct. It also verifies that no source data are surrounded only by flagged calibrator acquisitions, which for instance may happen if an antenna is shadowed. A message is given for information if problems are found, reporting about introduced flags.
Warnings, periods of observational peculiarities: If the observations were obtained in periods with special conditions or difficulties, a message is shown to inform about it and about the possible consequences in the calibration.