Calendar Time Zones

In TIBCO BPM Enterprise , each base calendar has a specified timezone (see the time-zone parameter to saveCalendar). This enables you to use different base calendars that apply to different locations of the world. Overlay calendars do not specify a timezone so an overlay can be applied to any base calendar without any conversion.

TIBCO BPM Enterprise stores all date-time entries, whether on a base or an overlay calendar, with a timezone of UTC attached. This does not mean that they are necessarily intended to represent UTC times. In effect, times are treated as timezone-neutral. For example, working hours entered as 08:00 to 17:00 on a base calendar with its timezone set to PST (UTC minus 8 hours) are stored as 08:00 to 17:00, not as 16:00 to 01:00 UTC. In most cases, this is completely transparent to the user, but you need to be aware of how TIBCO BPM Enterprise handles timezones and date-time values if you are making calls directly to the API.

Changing a base calendar’s time-zone value does not cause any adjustments to existing or future calendar entries. So if you define the start of the working week as 08:00 on Monday, it is still 08:00 on Monday even if the time zone of the calendar changes.

The start date-time values and end date-time values are timezone-neutral. When the system calculates the deadline, it applies the timezone specified when configuring the base calendar.

Time should be specified in this way for both base and overlay calendars. This enables the entries to be applied as if they were timezone-neutral any overlay calendar can be applied on top of any base calendar.