The Flash animation keeps improving with each season - as to be expected - but there's still a slight stiffness and disjointed feeling about it overall. The thing of it is though, I'm not sure if 9 Story is entirely able to adapt to the Arthur style: when you look at some of the new one-shot characters, celebrity caricatures, scenes and layouts, etc., it really doesn't match the shows style, I mean take a look at this screencap from Mr. Morris's upcoming episode:
It looks like he's in another animated series' universe altogether rather than the Arthur universe.
But on the subjcet of new episodes, Arthur's FB finally confirmed new episodes are supposed to air again the first week of June, but for some reason, different sources have only two random episodes of the current season scheduled, then a few from next season scheduled, so unless there's some kind of fluke or discrepency with scheduling, I don't know what's going on (though apparently, some international broadcasts apparently have lumped Season 18 and 19 together in one package, so maybe that's effecting U.S. broadcasts as well)?
In addition to Maria getting her own episode, it appears Season 19 will also bring back Carl again, for an episode with Rattles of all characters. Maybe it's just me, but Rattles kind of seems to be the current Creators Pet, doesn't he? We've had a few episodes lately where we see he's a lot more intelligence and cultured than his Tough Customer image makes him out to be, and apparently his and Carl's episode has to do with classical music, so we'll see how that turns out.