In Pennsylvania, we are making certain roads dual-named. We make sure to add the street with city name and state route without a city name as the alts. I’m finding that when saving and even re-loading, my adding of the street with city name isn’t retained. This will have a negative effect on routing.
Here is a screen capture (in Google Chrome Incognito):
To follow up on this, you may try updating the primary address before adding the alt address in order to avoid this issue - please let me know if this works.