Clarify backports note (dotnet#41937)

* Clarify note

* Change para to note

Author: adegeo

docs/core/install/linux-ubuntu-install.md

@@ -3,7 +3,7 @@ title: Install .NET on Ubuntu
 description: Demonstrates the various ways to install .NET SDK and .NET Runtime on Ubuntu. .NET is usually installed through APT.
 author: adegeo
 ms.author: adegeo
-ms.date: 05/14/2024
+ms.date: 07/29/2024
 ms.custom: linux-related-content
 zone_pivot_groups: ubuntu-install-set-one
 ---
@@ -28,12 +28,10 @@ This article discusses how to install .NET on Ubuntu.
 
 The following versions of .NET are supported or available for Ubuntu 24.04:
 
-| Supported .NET versions | Available in<br>built-in Ubuntu feed | [Available in<br>.NET backports<br>Ubuntu feed](linux-ubuntu.md#ubuntu-net-backports-package-repository) | [Available in<br>Microsoft feed](linux-ubuntu.md#register-the-microsoft-package-repository) |
+| Supported .NET versions | Available in<br>built-in Ubuntu feed | [Available in<br>backports<br>Ubuntu feed](linux-ubuntu.md#ubuntu-net-backports-package-repository) | [Available in<br>Microsoft feed](linux-ubuntu.md#register-the-microsoft-package-repository) |
 |-------------------------|--------------------------------------|----------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------|
 | 8.0, 6.0                | 8.0                                  | 7.0, 6.0                                                                                                 |None                                                                                         |
 
-<!--CULLED until the packages are available in the MS feed [!INCLUDE [linux-ubuntu-feed-sdk-note](includes/linux-ubuntu-feed-sdk-note.md)]-->
-
 When an [Ubuntu version](https://wiki.ubuntu.com/Releases) falls out of support, .NET is no longer supported with that version.
 
 # [.NET 8](#tab/dotnet8)
@@ -42,7 +40,8 @@ When an [Ubuntu version](https://wiki.ubuntu.com/Releases) falls out of support,
 
 # [.NET 6](#tab/dotnet6)
 
-.NET 6 isn't available in the built-in Ubuntu 24.04 feed. [Register the Ubuntu .NET backports package repository](linux-ubuntu.md#register-the-ubuntu-net-backports-package-repository) and use that feed to install .NET through APT.
+> [!IMPORTANT]
+> .NET 6 is available in the Ubuntu backports package repository for Ubuntu 24.04, and not the built-in package repository. For more information, see [Register the Ubuntu backports package repository](linux-ubuntu.md#register-the-ubuntu-net-backports-package-repository). After the repository is registered, use the following sections to install .NET.
 
 [!INCLUDE [linux-apt-install-60](includes/linux-install-60-apt.md)]