A bit unrelated but you might want to checkout this application note regarding ab1805. It provides external hardware watchdog (sounds like you might want that), deep power down reset (power off for 30 seconds if unable to connect to the cloud after 11 minutes of trying, as well as an external RTC. This might kill a few birds with one stone. I've had my new PCB with it for a month or two now and still have a bit to learn/implement but so far I'm very happy that I went to it. https://github.com/particle-iot/app-notes/tree/master/AN023-Watchdog-Timers
This is from @jgskarda thread. Let me know if you come up with anything on this.
- Glad you found that thread to.LoRa + Boron or B-Series. Is anyone else testing/developing? What's on the particle RoadMap? This might be my barrier or atleast a big hurdle for me to ever selling a product of LoRa + Boron. That said, you are still free to play for personal use with LoRa and Boron +Lora. I've also been told that as long as you don't operate both Radios at the same time then you don't necessarily invalidate the FCC of either the Boron OR the FCC on the LoRa Radio (assuming you are using one with an existing FCC listing). So in a use case where the boron connects once a month for OTA, I would think you can just turn off LoRa radio, Turn on the Cellular and then once done turn the LoRa back on. Although that feels pretty dicey and I'm sure a big gray area though and who's to know if the device ever operates with both radios active if only managed through firmware.