batch is used to generate multiple pdf files from one xdp template and different data fileshttps://experienceleague.adobe.com/docs/experience-manager-learn/forms/document-services/generate-multi-record-pdf.html?lang=en
What are they using ES4 for? Can you please provide the use cases for which ES4 is being usedthe reason I am asking is sometimes you don’t need to upgrade, you can just start using latest version of AEM forms depending on the use case
This article is for cloud service, but can be implemented for AEM Forms 6.5https://experienceleague.adobe.com/docs/experience-manager-learn/cloud-service/forms/prefill-azure-storage/introduction.htmllet me know if you need any help