There are a few interface changes that will require changes to your code, but it should all just be search-and-replace type stuff.
For almost all purposes you should now use realSources or realDestinations.
If you really need the old functionality then the old methods have been renamed to realSourcesOnlineOrInUse and realDestinationsOnlineOrInUse.
So why the change? The problem with the old methods, apart from their non-descriptive names, is that they behave in some unexpected ways for offline endpoints.
If you stop using an offline endpoint then that endpoint will still be returned in the endpoint list until some other MIDI configuration change causes the list to be updated. From a user perspective that means that offline endpoints can seemingly randomly disappear from the list when other things happen on the system.
The newer methods just keeps offline endpoints around as long as the application is open.
Obviously the original name was a typo, so it's been corrected.