So, the adults/parents etc. on At Attin genuinely think they are part of the republic and that contacting them is an option. Why do they believe that if the droid is clearly telling them that communications outside the barrier “isn’t possible?” Why do they even believe they’re part of a republic? I wonder if the planet is being controlled by an AI/Droid and it isolated the planet during the clone wars for safety or whatever. Also can’t help but wonder about Palpatines potential involvement with this planet and also if it has anything to do with the Sith fortune.
My personal hypothesis on what will happen next is that they won't go back to At Attin immediately. Instead they'll have another delay/side quest because either they'll have to repair the ship, repair SM-33, or KB's medical issue(s) will put her in danger and they'll have to find medicine. I wouldn't even be surprised if Jeb uses his Force abilities (if he really has any) to heal her when nothing else works. And of course there will be bounty hunters on their tail. Maybe one will put on a tracking device that will lead the pirates to At Attin. There's enough stuff in the show that feels like it's hinting at At Attin being lost since the Old Republic, but also stuff that only really makes sense if it's the High Republic.