Wirelessly posted (Mozilla/5.0 (Linux; Android 4.4.2; Nexus 5 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/32.0.1700.99 Mobile Safari/537.36)

Have we ruled out that it's simply based on the time between previous segment arrival and next segment departure? In the first example that is 6:05 and then 7:25; later we have an example where 4:03 shows as a connection, so the cutoff could be 5 or 6 hours. (Though it is surprising that this isn't 4 hours since that happens to be the usual maximum domestic connection time, which is a common case.)