Hi dnk100,
Sorry on the delay to get back to you on this.
As per a broader investigation, I suspect your issue may be related to an identified issue where the Boron’s NCP is not fully initialized. This can lead to assertion failures, among other issues, as the ICCID is read out as empty, causing some panic states when trying to connect.
If you code worked fine before and stopped working, I’d actually think it’s an assertion failure occurring in the device OS instead, and not your user application.
The initialization failure is not all or none. It can be intermittent and just come and go. That’s likely why you saw it working just fine with sudden failure. For now, when this happens, there’s no guaranteed way to get it working. But if you only power cycle by software reset, I don’t know that the re-initialization will ever occur. You’ll want to fully power off the device (removing all power for several seconds) before turning it on again for a chance to it to initialize properly.
You can find more info about the initialization failure in the lower part of Developer Support Update | Boron Pausing and Setup Concerns which discusses this issue.
We are still seeking to get bugfix out for this. The issue has been merged, but a binary of the device OS that deals with this is not out yet.