As a software developer (supply chain/ERP), the only constant is that code has errors and is hard to test. I can only guess, but due to all the random factors, testing pinball code must be a nightmare. We write testing scripts but those are only as good as how well you can control those factors. We have teams run those test scripts and document the results. Another group reviews and approves the test scripts and results. Even with this in place, a minor change can impact something you didn't consider or didn't find until it goes live in a unrelated area.
I can give Stern a pass if they are slow to update. At some point, you'll only get bug fixes and not new features. The risk is always more bugs or you break something else that didn't show up during testing. At some point, the code is "finished"...bugs and all.
That being said, I'd like more transparency on what's being worked on. I think it's better to communicate that even if it's just to say "we are only addressing bugs" or "there's no active development taking place." We might not be happy with the answers but at least we would know.