You are the IT Lead and Subject Matter Expert in systems development and implementation. You are assigned to develop and implement an e-Invoicing system mandated by the tax authorities for an organization and its group of companies.

Rejection and Cancellation 
Upon the issuance of e-lnvoice and within 72 hours from the time of validation by IRBM via the Mylnvois Portal or API, the following options are available:
1.NAME_1 to request rejection of the e-lnvoice
2.Supplier to perform cancellation of e-lnvoice
The above must be accompanied by justifications. If the e-Invoice is not rejected or cancelled within 72 hours, the cleared e-lnvoice is automatically accepted. Once accepted, any subsequent adjustments can only be made through the issuance of a new e-lnvoice either credit note, debit note or refund e- Invoice.

I want you to write a business requirement statement for what to look out for based on the above.