CODE EXAMPLE FOR PHP

customer io send_at api

{
  "to": "test@email.com",
  "transactional_message_id": "15",
  "send_at": 1644597600,  // unix timestamp format ex: ($date = new DateTime('2022-02-11 20:40:00'), $date->getTimestamp())
  "message_data": {
    "userName": "Kira",
    "userEmailAddress": "test@email.com",
    "StartDate": "test date",
    "TimeRange": "test range"
  },
  "identifiers": {
    "id": "2332"
  }
}