Thanks for reading the build this closely. You are right on both counts. The persistent bright moon line names the cause and not the flare, so a player who misses the 7 second opening line sits over visible shoals with nothing telling them what to do. Naming the flare in that line and keeping the full moon line pinned until the first flare of the night is a clean fix, and it goes to the build list as you wrote it.
The half an hour in our post was the time to Lantern Night. The first full moon is night 5, a few minutes in, and the post should have said that.