Using APERAK to confirm a truck appointment

In the previous scenario the Container Terminal, whenever agreed, can respond to the COPINO sent by the Inland Carrier with an APERAK.

The function of this message is: 

1. To inform a message issuer that his message has been received by the addressee's application and has  been rejected due to errors encountered during its processing in the application;
2. To acknowledge to a message issuer the receipt of his message by the addressee's application.

I have drafted an APERAK sample where the following data are available:

1. The reference to the COPINO previously acknowledged;
2. The reference of the truck appointment;
3. Start/End time slot for the truck appointment; 
4. The information related to the specified application error or acknowledgement.

UNB+UNOA:1+SENDER:ZZ+RECEIVER+110908:1130+1'

UNH+2+APERAK:D:96B:UN:ITG13'

BGM+11+3+9+AP'

DTM+137:201109081130:203'

DTM+64:201109091000:203'

DTM+63:201109091200:203'

RFF+ACW:00000001'

ERC+OK'

RFF+AEL:APPOINTMENT-ID'

FTX+AAO+++APPOINTMENT NR ?:APPOINTMENT-ID'

UNT+10+2'

UNZ+1+1'