When the support for Xamarin Native will be discontinued?
* You can see the official support policy -> https://dotnet.microsoft.com/platform/support/policy/xamarin
What is the exact release release for MAUI?
* See the roadmap -> https://github.com/dotnet/maui/wiki/Roadmap
What happens to existing build with Xamarin Native when MAUI is released?
* You would upgrade them to .NET 6 which includes support for building Android, iOS, and Mac apps with and without .NET MAUI.
What are the options for migrating Xamarin Native app to MAUI?
* There will be a migration tool to upgrade to .NET 6, at that point if you have a Xamarin.Forms project the UI would also be updated. If you aren't using Xamarin.Forms you would decide if you want to keep your existing iOS/Android UI or re-write with .NET MAUI. Your existing apps will continue to work.
When will the existing Xamarin Native app stop working?
* It will continue to work unless there is some breaking change in iOS/Android and it is after the support policy. At that point you would need to upgrade your project to .NET 6, but again this should be easy to do and there will be a migration tool.
Until when we can provide dev updates to existing Xamarin App?
* Not sure I understand this question.
If we did not migrate the existing Xamarin Native app to any other technology How long the existing app will work with the same code and environment setup?
* It will continue to work unless there is some breaking change in iOS/Android and it is after the support policy. At that point you would need to upgrade your project to .NET 6, but again this should be easy to do and there will be a migration tool.