All I know is if it ends up being blue I would just give them a bravo and a convinced golf-clap.
They made just so much teasing for it that is insane, a lot of things they did recently used red and blue theme that while not being related to red and blue mage at all could be speculated on, wich is exactly what YoshiP seems to thrive on.
I mean how about the guy during starlight saying I couldn't decide between the red or blue present so I got them both.
For all the people hoping in blue mage (I ain't one, my favourite FF jobs are all in the game already) that is such a cocktease.