Yep, rather intentional, from what I gather. I mean, I never heard anyone specifically say "We've intentionally made Bruchsal invisible on scanners", but I can only assume that it was on purpose. It makes sense.
Used to be that if you were hostile to the Bundies, Bruchsal would pop up on scanners just as you were taking the Mainz->Sigma-13 JG lane, which is a bit odd for a "pirate" base that's supposed to be hidden from the lawfuls. So making it an "invisible" object solves that problem, I guess.
But I had an idea about Bruchsal a while back. It's not entirely related, but I just thought I'd bring it up:
What if, in-RP, the Bundschuh realized "Oh crap, our secret rock-base is too close to the lanes, we need it further away from them", and they set up some plan to push the station a few klicks out into the asteroid field? In order to do that, they'd need some sort of tugboat-like ship, probably. So they construct a few powerful ships to shove their big-ol' rock out into space (Frankfurt would then be edited to put Bruchsal further out into the Taunusfeld), and then have a few big ol' ships left over. And... they use them as a basic frame to start making gunboats.
So I don't know if the Bundschuh want or need GBs, but hey, there's a neat little story for 'em if they ever come into existence. The Bundschuh kind of seems like one of those factions that needs some sort of real incentive for people to actually make a Bundschuh character, with their odd position in the Rheinalnd lawful/unlawful-ness and their lack of awesome equipment. Maybe a Bundie GB could get some more Bundschuh activity?
Yeah, okay, that's got nothing to do with this topic, really. But, y'know... just throwing it out there.