Why does TWILIO enqueue long-code messages for periods of time before delivery?


One of our clients today ran a test where they sent a message (using the NOTIFY API) to a large number of recipients

One of the recipients is reporting that she did not receive some messages. I asked her to send me a screenshot, and I can clearly see that some messages did not get received in the correct order (timestamp). I did some further digging and (while no errors or delivery failures), some of the messages did end up getting enqueued for some time.

I learned that during the time of the test there were large scale issues occurring were happening on a wide scale that encompassed all messaging coming out form our platform to US and Canada networks. The incident was regarding all outgoing communication on our system sadly so that caused lengthy delays for all users.

My first thought was that these lost messages were due to Carrier SPAM filters being applied, but I did not see any 30007 error message in the message logs for SMS that got filtered.

What would cause these delays? WITHOUT buying a a short code and WITHOUT using a 1-800 Toll free number, how can we send enable a group text session with multiple people (25 to 50, and upwards to 100 and even 1000) people all at once ... WITHOUT being flagged at SPAM by the carriers or experiencing network delays?