I recognize that you want to utilize the classic view within QuickBooks Online (QBO), legalgophers. Let me provide some insights about reverting to the previous layout.
QuickBooks has implemented updates to enhance and streamline the user experience, aiming to offer a better and more convenient platform. However, the option to switch back is unavailable. While some users may prefer the classic view, the latest version has been designed to provide improved functionalities and an overall smoother workflow.
Moreover, I will leave these articles if you want to know how to manage your invoice payments and other sales forms: