Some of that data was almost certainly sent encrypted. I'd be slightly surprised to find that their internal emails weren't encrypted at the transport layer. If

Some of that data was almost certainly sent encrypted. I'd be slightly surprised to find that their internal emails weren't encrypted at the transport layer. If they were using Exchange or even GApps, that'd be the default. It looks like a few individual mailboxes were popped. So even with a secure network, the result would have been the same.