Document Sequence for AP Received Invoices

Hi,

there is a new Spain Tax requirement to provide specific VAT details (Spain Online VAT Register (“Suministro Inmediato de Información”, “SII”), Release 12 (Doc ID 2273744.1)). One of post-patch step is to 'Document Sequence Setup (Mandatory Setup)':

STEP 4 — Document Sequence Setup (Mandatory Setup)

For the Payables (Received Invoice) and Receivables (Issued Invoice) transactions, complete the Document Sequence setup.

May you please advise on the steps to proceed with AP invoices sequence numbering? Any suggestions/ lessons learned from your experience would be helpful (like whether automatic, manual, gapless, etc). Also is there a way to have sequence just for one Entity's invoices? if not, what about Operating Unit specific?