I foresee a button somewhere to re-load the queries in tfs. I think you cache the queries and execute them,
and  not execute the queries at the tfs server.
 
Situation
I made a subfolder WIP in WorkItems, and underneath this sub-folder I have a couple of queries, representing a status I want to follow, for a sprint.
Now when I go to the next sprint (every 2 weeks) I update these queries so they look at the new sprint too.
but VisualWip still has the old definitions, so displaying the previous sprint. for the moment I just close and open Visual Wip, to bypass this.
 
Not a big problem since it only has to be done once every 2 weeks, but one may not forget it ;-)
 
Ruben Willems