The names of date fields in the Routable API will always be postfixed with _on (e.g. due_on, issued_on). Dates are recorded in the [ISO 8601](https://www.w3.org/TR/NOTE-datetime) format: YYYY-MM-DD.
The names of timestamp fields will always be postfixed with _at (e.g. created_at, approved_at). Timestamps are recorded in the longest-form ISO 8601 format. Timestamps in API responses will be normalized to UTC, and timestamps in requests must include timezone designators. The format used is YYYY-MM-DDThh:mm:ss.sTZD, for example, 2019-07-09T15:03:36.1234+00:00.
In these format strings:
YYYY = four-digit year
MM = two-digit month (01=January, etc.)
DD = two-digit day of month (01 through 31)
hh = two digits of hour (00 through 23) (am/pm NOT allowed)
mm = two digits of minute (00 through 59)
ss = two digits of second (00 through 59)
s = between one and six digits representing a decimal fraction of a second
TZD = time zone designator (+hh:mm or -hh:mm)