We are currently working on defining an approach that will work for all devices moving forward.  It is important to understand, however, that this functionality CANNOT simply be implemented in a CSP alone since there is no underlying OS functionality/API for the CSP to access to make this happen.  We have a bunch of one-off requests from various customers to do just the sort of thing you suggest.  Rather than implement each one individually, creating custom mechanisms each time, we need to define a strategy with enough extensibility to handle all such requests we can reasonably envision customers asking for later.  And then we have to implement that strategy.  And that will require core OS changes that likely will only occur in Kit Kat and beyond since we are actively discouraging releases of major new OSes based on Jelly Bean.  When we implement, we might not implement every possible combination, but at least we can ensure that we implement within an overall design that can easily expand to handle other cases without major rework.  All that takes a while.  So, the best I can say right now is "stay tuned".