What about this?
this is in the important.txt/readmeh.txt of the latest rxtools nightly:
If you have a New 3DS, use 0004013820000002.bin from ReiNAND v2 (search for Reisyukaku's pastebin) instead of firmware.bin and put it in /rxTools/data/.
Blah. 3 of my NSO + Expansion Pass family group members are leaving. Found one replacement so far but still need to fill two empty slots. I have 9 days or i eat the extra cost myself. But with a full group $11 for a year is a good deal. imo