You know how in duty finder, it won't let you do Expert mode until you have certain dungeons unlocked?

So too with BLU - until you go out and learn certain skills, you cannot progress. Nobody's upset because certain dungeons aren't available to them. They'll just ask their FC or in the forum or wherever, "which ones am I forgetting?"

Besides, it's not like all of BLU's spells won't be uncovered the first week anyway just like Eureka was.