@midna @fish yeah.
+1-804/222-1111 is the old #MCI #Worldcom testing line.

• for #Iridium, there's +1-480/752-5105 as their testing line.
• #Inmarsat uses +870-776/999-999.
• On #Thuraya it's just 11112.

https://globafone.com/test-your-device/

Basically every #MNO and/or #MVNO has #TestingLines, it's just that they don't get published.