The Windows Insider program of Microsoft no ISO images for the Fast Ring are released. There have been some exceptions, but usually ISO images are only released through the program's Slow Ring.
So Insiders who are registered in the Fast Ring, have a problem, especially if they want to perform a clean installation using the ISO of the new operating system.
Below we will talk about the UUP Dump, a tool that will help you obtain the ISOs from Fast Ring, immediately after their release by Microsoft.
According to project developer abbod1406, UUP Dump is an automated command script for editing Windows 10 Unified Update Platform UIP files. The script allows you to download and convert upgrade files into a usable format (ISO or WIM).
Let's see how you can use UUP Dump to create a Windows Insider Fast Ring ISO.
From address https://www.uupdump.ml/, select Fetch latest build:
Immediately select the architecture you want (x86, x64, arm64) and click Get Updates
Click on the download name you see above and in the following screens you will be able to select the language and version (Home, Home N, Pro and Pro N)
Selecting "All editions" will download the files needed to create a multi ISO.
The next screen will allow you to download the selected files.
Select “Download using aria2 and convert”
A ZIP file will be downloaded. Save the file, and unlock it by right-clicking on ZIP. Select Properties, then Unblock
Export the contents of the ZIP file by right-clicking and selecting Export All. If you notice an error while exporting the ZIP, do not pay attention, press skip to continue the export.
When the export is complete run the file aria2_download_windows.cmd:
Registration in iGuRu.gr via Email
Immediately after the UUP Dump will download the UUP files. When the download is complete, the files will be converted to ISO automatically.
You will find the ISO in the folder where you exported the ZIP file. That was it, enjoy your new ISO.