Per the CBSA:
Empty conveyances in the air and marine modes of transport are currently exempt from transmitting pre-arrival/pre-load data; therefore, they are exempt from transmitting the CACM.
However, if a
carrier (conveyance owner/operator) choses to voluntarily transmit an
electronic ACI conveyance report for an ACI exempt conveyance, the
CACM must be transmitted in order for the arrival status in the CBSA system to