So far 3 people in this thread are reporting exactly the same problem. All 3 are using the 1030.

OP said this began during or after a group ride. Can anybody else comment on whether that seems to be involved? I wonder if it has anything to do with all the chatter from all the sensors and head units. Shouldn't, but who knows?

I agree temperature shouldn't affect it, it's possible the software in the Garmin does something at certain temperatures and not at others, and there's a bug in that code that takes the networking stack down temporarily.