AX 2012 Free Text Invoice Number - No unique reference until posted?

All,

Probably a silly question. While the Free text Invoice is in a ‘Draft’ or ‘Unposted’ status is there any FTI number to refer to it by? (An FTI number is generated only after posting / double entries are created - Unlike a newly created SO / PO / Voucher where the unique number is generated instantly). So if I were to ask a consultant / user / developer to check FTI XXX for issues as its NOT posting, what do you substitute XXX with in your organisation?

Thank you