User blog comment:SayuriDarling/The Trials of Apollo Official Discussion/@comment-24067344-20151023013713/@comment-1515612-20151023023513

Either his publisher is pushing for this or something. BUT he also left The Blood of Olympus with a lot of plot holes so it makes sense. I don't get why he's doing two series at once either unless he wants to take a long break in 6 years (which it seems like that's what he will do).