Two 3G Borons stopped updating particle cloud though "breathing cyan"

I have two 3G borons that have been working fine for a week or two. Last night one stopped reporting to the cloud. 10 hours later the other one stopped reporting as well. They are “breathing cyan”. Diagnostics only say the can’t be contacted. Anyone experience a similar problem?

(I haven’t tried resetting or any manual intervention because these are running unattended.)