I had the same exact issue as Blvck. It was failing on (NFIRM) : v.24368 -> v.03553 every single time I tried (10 attempts). EmuNAND was on v11, and I couldn't find any advice outside of trying NTR.
I had been using version 5.2 of Luma3DS, and everything was working fine, but I noticed that 5.5...