All dates and times in requests to and from SignalWire API are UTC, and presented in RFC 2822 format.
For example, the date and time of 8:01 AM CDT on July 23rd, 2018 is presented as:
Mon, 23 Jul 2018 13:01:00 +0000
All phone numbers in requests to or from the SignalWire API are in E.164 format, an unambiguous general format for specifying international phone numbers. Numbers in this format start with a plus sign ("+") and the country code.
For example, a US-based phone number like (555) 123-4567 would be formatted like: +15551234567.
If a number cannot be represented in E.164 format, then SignalWire uses the raw Caller ID string that was received.