Hi @briant94284829
Perhaps there is a new external website that traffic is going through that is only applicable to iPhone. Something like Apple Pay or a site that is only used with Iphones....
1st question - Is there a reason why you have the Internal Channel set to Override? (Normal practice would be to have this unchecked, but there are reasons/exceptions)
2nd question - What do you have the Last Touch Detail set for the Internal Channel? Maybe there is a clue here?