Default [Q] Can I downgrade to try Saferoot?

I came across this thread recently (I own an S4 as well) and I wondered whether anyone had tried this approach on a Note 10.1 2014.

Unfortunately, I recently upgraded to Kitkat and I'm now running ND2 so it won't work for me. Can anyone tell me what the earliest ROM version I can downgrade to using Odin (if I can downgrade at all) without blowing the Knox fuse.