c52b1065_User_Guide___Groupcall_Support__Description
[Message Status] Messages delivered to handset [Notes] There may be a short delay, especially for large distribution lists, between submitting your message and it being sent by the SMS sending provider. You will see a status of 'submitted' until the message is either delivered or another status is returned. [Description] 
Message has been delivered successfully.
Messenger v5 User Guide | Groupcall Support
Description