I seriously don't know. There are many places you can train. I mean you can walk into any grass to train if there are high enough Audinos. Just find the highest area, give it a Lucky Egg train there when you can't spam levels in Join Avenue shops.
Closing this since this is pretty much the only answer that will appear if not similar to all possible ones. Any future questions should be directed to the Quick Questions for B2W2. For more in game team help, please visit the Battle Center.