With the entry into operation of the G4 Declaration of temporary storage, it is necessary to take into account in the declaration of low-value shipments (H7) in the PreviousDocument box, the following:

1. Temporary storage declarations (TSD) may be G4 declarations or summary declarations for temporary storage prior to the Customs Code of the Union (DSDT). 
2. G4 Statements: It will be known that it is such a statement when:
   1. the value G4 is declared in positions 5 and 6 of the MRN of the G4 declared in PreviousDocument.prevDoctRefNum and has a length of 18 characters (example 24ESG4A000000000U6: the MRN is the first 18), or,
   2. When the length of prevDoctRefNum is 12 numeric characters (scale number), for example, 28012400000

   In both cases, the batch number after the MRN or the stopover number will NOT be declared in the PreviousDocument (prevDoctRefNum) box, even with 00000

3. DSDT statements. It will be known that it is such a statement when:
   1. The length is 23 characters and in position 11 it has the value 8. Example; 18ES0028018000123600002, or,
   2. When the length of prevDoctRefNum is 16 characters (scale number) and the first 11 are numeric (2801400000100002)

   In both cases, the batch number declared after the MRN or the scale number MUST be declared in the PreviousDocument box (prevDoctRefNum) and cannot be 00000 (from position 19 or 12 respectively).

4. Other considerations:
   1. Cannot declare + (plus sign) in referenceNumber.
   2. Temporary storage declarations (either G4 or DSDT) that have flight number as reference:
      • It is considered as such when the first 16 characters of prevDoctRefNum contain numbers and letters specific to the flight date, company and flight number, or if it is a G4 declaration that does not comply with the format of point 1 a) or b).
      • In these cases, it is recommended to declare document 5026-dated by knowledge number to report the knowledge number. It is not necessary to declare it in other cases.
      • It is NOT recommended for this type of DSDT reference number per flight number to declare in prevDoctRefNum, for example, the flight number and bill of lading number. If the knowledge number is declared in prevDoctRefNum and also 5026, it can cause problems when dating. It should be declared separately as follows:
        • prevDoctRefNum: flight number.
        • 5026: knowledge number.
   3. Document 5025 provides information on the shipment number in the transport box. This is always mandatory.