I should say that unless it's unequivically stated in an 'approved' document somewhere that the displays are CAS, then the approved speeds are IAS and the displays are IAS.
Even on our aircraft where the displayed speed is within a knot of CAS, we call the various scheduled speeds "IAS".
What I meant was that the ADC vendor will probably say something like "XYZ Inc's whizz-bang ADC displays CAS, altitude and the phone number for the cute pax in 3A" in their sales brochure.