Hi @DS2022 , Kindly note that the sequence should follow the generation order not submission order. Moreover, there are no limitations on uploading/sending simplified invoices to ZATCA, it can be uploaded to any order as long as they are generated on a sequence, and the sequence will be validated on the backend, so it’s not a (real-time validation).
Ex: if invoice 1, 2, 3 were generated in a sequence, it can be submitted as invoice 2,1,3.
So there is no need to do an extra step to modify your PIH if your EGS generating your invoices in a sequence, however, any identified gaps on the sequence compliance during backend validation, will be submitted to further investigation by ZATCA and may result in penalties if found to be non-compliant.