Parent/child iterations info in RRDI Data Model

Hello,

I have following iteration hierarchy in RTC:

Release 1
*Sprint 1
**Analysis
**Development
**Testing
*Sprint 2
**Analysis
**Development
**Testing

Release 2
* Sprint 1
** Analysis
** Development
**Testing


I want to filter particular Project, then Release, Sprint and particular iteration. Ive observed CCM reporting data model https://jazz.net/wiki/bin/view/Main/CALMReportingDataModelDetails and found
REST API resource: iteration REST API Property: parent
but there are no related DB2 table, DB2 field, FM Model table, FM Model field entries.

What does it mean? Do we have plans to extend FM model to provide this information?

-thanks in advance