For a database from-file or to-file, if a MBR parameter is specified on an OVRDBF (Override Database File) command, then the override member name is used instead of the value specified on the copy command. If the TOFILE parameter is specified with no MBR parameter value on the OVRDBF command, then the first member (in creation order) in the database file is used instead of the member specified on the copy command. For a diskette or tape from-file or to-file, if a LABEL parameter is specified on an OVRDKTF or OVRTAPF command, respectively, the override label name is used instead of the label specified on the copy command.
If you copy multiple members or labels to corresponding like-named to-file members or labels, then you cannot use an override to a single to-file member or label unless you also override the from-file to a single member or label.