This setting should typically be set to Pull for standard integrations, regardless of the connection used between Pacejet and the ERP. Any value other than pull assumes that a customized (non-standard) print configuration will be implemented.
Using the value Pull sends print jobs to the Pacejet Print Connector, which then sends them to local/networked printers.
Accumatica and Plex users will use the API setting because these ERPs control the printing through their application.