We generally do not include country-wide swathes of controlled airspace when it is widely-known that all airspace above a certain altitude is of a certain class. Does VFR flight commonly occur in the class D of which you speak?

I can't see controlled area in FIR WARSZAWA above FL95 on skydemon

by AIP POLAND ENR 2.1 Controlled airspace includes: controlled area from FL95 to FL660 - class C