It is (most probably) not cached within the app, but somewhere in iOS. These cached files typically expire at some point in time - after which loading the track set will go back to the server to find the updated version. Don't ask why the change is not detected directly, I have changed to policy to check the server directly for the next version already. In case you can wait some days, just try again later. Otherwise, I'd need to change the file names to force a new load. Updating the list is not needed / helpful as longs as file names are not changed.
Sorry for the pretty technical reply, short version: it will resolve over time automatically.
- Harry