If you need to connect more than three internal modules?

Since the maximum number of internal modules you can connect to a single base station is three, there is a way to have more, sort of...  

You can add another base station to an existing account, this way you can have access to an extra three internal modules just by switching to the second station, its fairly simple and seamless, this video here should explain it a bit more.

https://youtu.be/Ijb611fZwe0