@Guzzist, my comment is not intended to raise confusion but to eliminate it
Like I said, Offline maps and Offline navigation are separate things.
Offline maps is intended to prevent the need for downloading map tiles on the go. You can download them in advance, so there is no need to download them while riding. Therefore, whenever available, your offline maps will be used. If not available, they will be downloaded on route afterall.
Offline navigation tells the app to do navigational calculations by itself, without help from online (Here) services. Of course to be able to calculate navigational routes depends on the availability of offline maps, but it is not mutual exclusive.
So:
You can navigate online, without the need for offline maps
You can navigate online, including the use of offline maps.
You can navigate offline, completely depending on pre-downloaded maps.