Thanks, SES.
"Provisional" and "Composite" were widely used WW II Allied terms that were often affixed to unit designations. There are many examples of this. Yet, in English-to-German Allied military dictionaries from the WW II era, neither word appears. I am looking at my copy of
TM 30-506: German Military Dictionary (War Department, May 1944) right now. Evidently these two terms puzzled the compilers of the dictionary and they provided no translation into German. That's especially curious since the term "zur besonderer Verwendung" was widely used by the Heer and the Luftwaffe, particularly the latter. As you know, many Luftnachrichten units, mainly the small specialized ones, used the "z.b.V." designation for the duration of the war. So I must conclude that duration of existence was not always the determinant in affixing "z.b.V." to a unit's designation. It meant something more than just "Provisional".
Larry