change management: change state by time

[fight12]

Hi,
i'm working with the ITSM::Change Management module and i want to add a new condition to every change but i don't know how to achieve it:

I want the CHANGE STATE value changes the value automatically when the PLANNED START time is reached. I've created this condition (in 'Expressions') but I don't know what value i must fill in the VALUE field:
OBJECT: Change
SELECTOR: number of change
ATTRIBUTE: Planned Start
OPERATOR: is
VALUE: ??? (I don't know the system variable for indicate the current date)


If there is another way to achieve it please let me know.
Currently i have read some official documentation like http://doc.otrs.org/itsm/3.2/en/html/ch08s05.html with no success.

Thanks in advance,
Regards

[fight12]

Hi,
If you need more information please ask me. I only need that a Change changes its state automatically when arrives its planned start time.

Thanks!