GlideUpdateSet.set() to make an update set the current update set does not work in business rule

[Snow Tomcal]

we are trying to send an api call from one instance to another and create a bussiness rule and make it current on the reciveing instance(thye api call sends the user name relevent for the update set and the bussiness rule impersonates to this user and then uses the GlideUpdateSet.set() api function to make the update set current)

[Ankur Bawiskar]

@Snow Tomcal 

what's the business requirement you want to achieve?

[Snow Tomcal]

We created a button on our PROD instance.
We want this button to create a new Update Set on the DEV instance. It works FINE.

However, we don't know how to make this new update set as the current one for the user who clicked the button.

Our code does not work from a Business rule but if we run in in the background - scripts it works.
How does the functions GlideUpdateSet.get() and GlideUpdateSet.set() work? 
In which tables the data of the current update set is stored?