For a bit they, at least GM Joel stated almost every other week, that they were working on making the World Bosses rotate so that all would be available at each World Boss Time. When I asked GM Sirbianco, I was told there were no plans for it, but they would take note of it. I guess having us allowed to do a World Boss when we can is better then nothing. 😞
I agree there are better times to have the world bosses, but since that Not going to happen, please let us at least do each world boss at the time the developers decide to have them.