So yes, if they wanted to, they could move the WBT alone (not WBT-FM) calls to 107.9. But not while they are still on 1110. There hasn't been any rule changes making WBT-AM a legal set of call letters. So even though nobody at the FCC would really care if they ID'd 1110 as either WBT Charlotte or WBT-AM Charlotte (not both), Since they NEVER say WBT-FM Charlotte the 107.9 frequency isn't being legally ID'd. OR, do they sneak it in somewhere else? They could have dropped it in between two elements in a stopset
