When I checked the repo, I see it says they removed support for the Primo. I will be honest, when it saw "PrimoLowPower" in the examples list, I was not aware there was a board called "Primo", and just assumed they meant it was a primo low power state, like the lowest power state you can get to. So, it was only the Primo that reset then. Apparently the version of Arduino Low Power that gets installed in the IDE is not up to date with the repository, because it still includes the PrimoLowPower example.