When sending incoming SMS messages to a URL, if the receiving server is offline or unavailable then the messages do not queued up and re-sent. I'd like to see this feature look for a HTTP 200 message to confirm the message was successfully received -- if not try again every minute for the next 10 minutes. If it still fails, then being able to see ones that failed in SMS History with a retry button would be helpful to ensure no messages were missed by the integration.