Your brother should hire a criminal defense attorney experienced in DUI cases. You are right, there are new developments in this area. If this is your brother's first case his attorney may suggest a program known as ARD.
The ruling in Dauphin County could well explain the delay. It would be wise to consult with experienced counsel now to be prepared. Counsel could also communicate with PSP. Most of us here, myself included, offer free consultations . Really makes sense to be prepared. Good luck.
I concur with my colleagues, that your brother should contact an experienced defense attorney. Although, the police are a little "shell shocked" due to the recent Superior Court decision rest assured they will eventually come to their senses and decide what to do with the outstanding investigations. Be advised that there is a subsection of the DUI law that only requires the Trooper's opinion as to the capability of a person to drive safely on the roadways of the Commonwealth.