Yes, it has been known to be variable for a long time.
But these variations appear to have changed lately. That is very unusual. Most stars do not change their behavior unexpectedly, except for a few exceptions, like flare stars or the so-called "cataclysmic variables". What we may be seeing is a phase state shift from one level of dynamic equilibrium to another. This may be evidence of a fundamental change in the star's interior, perhaps a herald of some violent outburst soon. Of course, "soon" in astronomy can cover a lot of ground.