Hi, uploaded the QC4-Firmware for you at MEGA: ALL_TFN_S550TLUDU2AQC4_S550TLTFN2AQC4_CL10915988_QB12975214_REV00_user_low_ship.tar.rar (This Firmware is not rootable atm, and works only with revision 2)
Flash it via ODIN in the AP-Slot.
It is ro...
that boot is not signed for my device, I have the Walmart Family mobile variant build number MMBK29K.S550TLUDU2AQC4 with 6.0.1. Has anyone successfully rooted that one yet?