With the current Internet database resources online available to patrolling police while in the car, they can run plates in 3-5 seconds. This query of info would yield those DUI restrictions. Just an FYI.
Likewise they can do this while in a restaurant or pub parking lot and run the plate records against the state and national database for the whole parking lot in about 10 minutes. This was true for about 60% of police forces 10 yrs ago when I was involved in documenting the GUI as a technical writer for (a div. of Motorola) in the public safety industry. I would guess that nowadays, it's more likely to be at 90% of the urban area police forces that have the capacity - without needing to call the query into the dispatcher.
Personally, I see no need to make an alternative plate and see dubious constitutional issues as to changing status to a DUI plate. Something about 5th Amendment issues..smells to me..but admittedly I'm no lawyer.