Depends on the market for iHeart. In Chicago, they shifted 95.5's Country format to HD2. This is common practice in larger markets with format changes.

WKSC HD2 for whatever reason showed up in the ratings in this book. Nothing special, but I've never seen it show up in the actual ratings before beyond simple cume. They all get at least some cume, usually between 5,000 and 15,000. Not usually enough to break a 0.1. Again, nothing special, nothing they could make money with

In other markets, if they have an AM station that doesn't have a translator, they frequently put them on HD2.

Majority of the rest of them are stream simulcasts as you mentioned. Some (Like WVAZ HD2) clear their BIN (Black Information Network)

WLIT HD2 was acting as a way to keep other stations from using "The Breeze" brand until earlier this year. They had numerous subs across the country running the same feed. They obviously are not worried about that branding anymore like they were 4 years ago, since they began shutting them down. This is why WLIT HD2 is no longer on the air.

Is WGCI HD2 still operational? Haven't heard it in awhile. Was running their corporate Dance log with a Legal ID last time I heard it.