Document numbering only after submitting

Hi all,
Currently we have the following issue as documents are numbered when you click save and if not submitted for Tax purposes those documents will be seen as DELETED (bribe, etc).

Can we think of moving the autoname series (Ext_name) as the last to be run when submit is done!

For example
Sales Invoices SI-2019/0010 (Submitted)
Sales Invoices SI-2019/0011 (draft)
Sales invoices SI-2019/0012 (Submitted)

When doing SAFT for tax the numbering will not match as SI 0011 not included… While if we number NAME without series and field Ext_name (autoname series when submitting)… When submitting SAFT will contain submitted docs and the correct numbering.