Here's some info quoted from "Fighter Aircraft of the 1914-1918 War"
by Lamberton and Cheesman:
Although the former (aew: D-VI implied here) type proved quite promising
the success of its more powerfull relative the prototype Fokker D-VII
in the fighter competition of January 1918 rather overshadowed its
developmeny. Trials of the prototype took place in March 1918, and a small
production order was placed for the D-VI, as it was designated, probably
as a precaution against the possible failure of the far superior D-VII.
D1631/18, the first production example, was delivered on April 26th,
1918. Like the V.13/1 prototype, it had the 110 h.p. Le Rhone rotary; ...
Later it goes on to say:
From late April to August 1918 a total of 59 D-VIs were delivered
(D1631/18 to 1689/18).
and....
Seven examples, 1632-1635, 1641, 1642 and 1644, were supplied to
Astro-Hungary in august 1918.
the type equipped or partially equipped some Jagdstaffeln during the
summer months. When sufficent D-VIIs became available, the remaining
machines were relegated to training duty.
Hope that helps! Now I have to dig out my 4-color Lozenge decal sheets!
-Al