Boy, that is an odd combination, nostalgia most of the day and Imus in the mornings!
Sounds as though they might be testing the waters in search of a format change.
760 out of Tequesta started out with a music format (believe it may have been adult standards) when they hit the air in the the late 90's (I think that was the time frame) and at any rate the music didn't last more than half a year or so before they switched to the current sports format).
Clearwater's WTAN a graveyard station at 1340 also airs Imus, the rest of the day they are brokered programming, but in periods where they can't sell the air time, they do "Music of Your Life", that stange as well.