Right. It must be able to use current maps to be of use in the future.However, how does that affect map updates for current devices? Even if an updated map is available for a device, if the matching map is not available for BaseCamp (doesn't transfer from the device after it's updated), very bad things happen when you try to plan a route. I found this out recently after updating my device but not knowing that I have to separately update the maps in BC to match. I planned a long route for the wife and I from IL to NC and back. It randomly dropped multiple fuel points from my routes and we had a terrible time navigating. Between her motorcycle and mine, our max range was 150 miles on a tank. I had every fuel stop planned to accommodate that. We had to figure out fuel stops on the way instead. If no map updates for BC are available in the future, you will be either limited to the current map on your device or BC will quickly become effectively useless.
Most likely Garmin will not change the map format but there is no guarantee especially if they start officially calling it "unsupported".