Run regedit command to open Registry Editor.
In left pane of Registry Editor window, navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsSelfHost\Applicability
How to switch Windows Insider Channel in Windows 11
You should be able to locate BranchName registry string (REG_SZ). You can set it to channel name like Dev, Beta and Release Preview to opt for respective Windows Insider Channel.
Then go to following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsSelfHost\UI\Selection
How to switch Windows Insider Channel in Windows 11
Similar to step 3, set the UIBranch registry string (REG_SZ) to Dev, Beta and Release Preview. Make sure you fill same Value data for both the registry strings.
Once done, close Registry Editor and reboot.