With the merger of DM-18643 (implementing RFC-589), the configuration options for single-frame astrometry (AstrometryTask) have changed.  This fixes various bugs where (a) selections of the reference catalog were performed only in some modes of operation; and (b) multiple conflicting selections of the source catalog could be performed in some modes of operation.  All obs package defaults have been updated to reflect the new changes.  You will only need to worry about these changes if you have overridden the obs package defaults.
In summary, the following changes have been made:
- Source selectors have been removed from the matchertasksMatchPessimisticBTaskandMatchOptimisticBTask.
- The source selection is now handled consistently by the AstrometryTaskorRefMatchTask. Furthermore, source selection only happens once, rather than being repeated for each iteration of the match-and-fit-loop.
- Reference selection is also handled by AstrometryTaskorRefMatchTask.
- The source selector and reference selector in the AstrometryTaskandRefMatchTaskare calledsourceSelectorandreferenceSelector, replacing the oldsourceSelectionandreferenceSelection(both of which were inconsistently applied).
- Note that the sourceSelectoris asourceSelectorRegistryso should be set by applying (e.g.)config.sourceSelector.name = "science"rather than the oldconfig.sourceSelection = ScienceSourceSelectorTask.