SharePoint Add-in retirement :Possible path to migrate a hosted add-in

In reference to this article here - https://learn.microsoft.com/en-us/sharepoint/dev/sp-add-ins/retirement-announcement-for-add-ins

I would like to know the possible options to replace existing SharePoint add-in's using SharePoint Framework and the path to migration. 

A little background:

We have a SharePoint Hosted Add-in developed using knockout.js which is a form application that does CRUD operations and also has a XAML workflow for approvals. It is packaged as an app via the app catalog.

Is it possible to re-use the existing add-in and deploy the solution using SharePoint Framework or is this application need to be re-built using the SPFX webparts? Any help or guidance is greatly appreciated. Thank you in advance.