Applications which are named UF*, UM* or UR* are always a part of the ECU´s "monitoring concept" or "function monitoring".
MAPs and values which are named *_UM are values of the "function monitoring" (Funktionsueberwachung).
MAPs and values which are named *_UC are values of an early stage of a "command test" (Befehlstest), set by an applicateur to test the results of the "function monitoring" with fixed values.
Please have a look to app "URCPU - EGAS Ueberwachungskonzept - Befehlstest mit Ebene 2" at page 1773 of the german MED9.1 TFSI Funktionsrahmen,
or page 1051 of the english Alfa ME7.3 function sheet.
I think there was no potential for any kind of tuning.
Thank you! So basically, all the _UC maps are used only in the factory and are never activated during normal car use?