SMS Mass Messages (broadcast) request

{
  "recipients": [
    {
      "phone_number": 380961111111,
      "extra_id": "AD-6640-7006",
      "name": "Michael",
      "greeting": "Mr. "
    },
    {
      "phone_number": 380962222222,
      "extra_id": "AD-6640-7007",
      "name": "Zoya",
      "greeting": "Ms. "
    }
  ],
  "callback_url": "https://send-dr-here.com",
  "start_time": "2020-12-12 10:10:10+03:00",
  "tag": "Campaign name",
  "channels": [
    "sms"
  ],
  "channel_options": {
    "sms": {
      "text": "Dear %greeting% %name%! Here is an SMS",
      "alpha_name": "GMSU",
      "ttl": 300
    }
  }
}