WRT1900ACS Partitions - both marked "Alternate" Can't switch

I went looking for the cause of the WARNING message that cropped up on a couple of my builds that elicted my post on this topic.

I came up with this OLD Forum topic:

that then led me to this Commit:

Now, based on the commit, it makes no real sense this caused my issue. It's just padding to make it work, but looking a bit more, the warning references the /luci/Packages and concerns only the LuCI feed. Add to that my build begins to work ONLY after I take a LuCI feed update??? I'm really curious. Anyone.