Update Variable Value dynamically

Hello I am using GoodData for our application. My question is related to variable and update its value dynamically.

I will explain you what I have done so far.
I have created variable with name organisation_id and set type to filter variable and selected attribute as a id column of one of our database table (Please check attached image - 1)
After that I have set user-specific value for that variable 
e.g. organisation_id = 12, 34, 56 etc.

After that I have create custom matrix and use this variable in MAQL
e.g. 
SELECT COUNT(id) WHERE organisation_id
(Please check attached image - 2)

And then I have added this matrix in insights and in the widget and it filter the data which related to value of organisation_id variable i.e. it only display data related to id - 12, 34, 56 

My Question is:
Can we update variable value using API?

like in above example we set organisation_id = 12, 34, 56

now I want to update organisation_id = 89, 90 and get result related to 89 and 90

Instead of updating organisation_id value from variable setting can we update it using API?

**I embedded the dashboard using iframe**
basically before loading iframe can we update variable value using any inbuilt API of GoodData instead of updating it manually from variable setting page?