Notcom has released TinyUmbrella 5.10.03 update that includes support for Apple TV 4.4.3. By using TinyUmbrella 5.10.03, you can save SHSH blobs which are required for untethered 4.4.x Apple TV jailbreak.
See also:
How to Save SHSH Blobs with TinyUmbrella
How to Downgrade iOS 5.x.x to iOS 4.3.3 with TinyUmbrella
Download TinyUmbrella 5.10.03 for Windows
Download TinyUmbrella 5.10.03 for Mac
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