Glad to hear your Garadget is performing well.
The offline notifications are sent based on what Particle reports to my event processing code. There could be multiple reasons for device momentarily disconnecting: short DHCP leases, radio interference, power noise, Particle's network etc.
I'll consider filtering out events by delaying the offline reporting for several seconds and cancelling it if device comes back online in that time. I'd like to hear if anybody else gets frequent offline notifications to get the idea about the priority of the issue.