These docs are for an old release. Info on upgrading to v5
edit doc

timeZoneParam

A parameter of this name will be sent to each JSON event feed. It describes the timezone of the startParam and endParam values, as well as the desired timezone of the returned events.

String, default: 'timeZone'

The value of this parameter will be a timezone string like "America/Chicago" or "UTC". For local, it will be unspecified. See the timeZone setting for more info.