While @NiLuJe’s working on the new jailbreak package, here’s the KT4 factory firmware 5.11.0.
https://mega.nz/#!nnhGGISZ!NRIEbwAPT...cPV5B-tL1-75lM
md5: fd3e7ed8ebea59432163a5e713cd90c5
sha256: 64a8891cba9af919af5b9b4d4ee5550305c0fda07c94e9132b 5e4d9f945e2f51