[INM@RLM]

This post links directly to #73 above and only indirectly to the new edition of 'Zerstörer'. It is placed here only as another example of why not everything in Mankau & Petrick should be taken as gospel. Since this topic is super-nerdy, best perhaps that most readers save their time and stop at this point.

There is a small error in the M&P statement "As an emergency measure Messerschmitt consequently fitted 13 Bf 110 D-0s (W.Nr. 3321-3324, 3336-3344) with ETC 500s, removing the belly tanks in the process." The last aircraft, WNr. 3344 was not in fact a D-0/B since Matti Salonen's database of Lw losses records WNr. 3344 as Bf 110 C, G9+MM, that became a total loss with 4./NJG 1 on 27-Apr-41. Since the D-0/Bs were only slightly less rare than hens' teeth, and all were required immediately to equip two Staffeln of Erpr.Gr. 210, the survival of even one machine to subsequently serve as a night fighter smacks of the purely whimsical.
In reality then just twelve D-0/Bs were delivered in June 1940, making a total of fourteen in all, not fifteen. These then were: WNrn. 3167 in April, 3175 in May and 3321-3324 (4) & 3336-3333 (8) in June. [All M&P p.182]

It's not possible to confirm the total of Bf 110 D-0/B deliveries directly in any RLM Delivery Plan because of the reclassifications ordered by the Lw. General Staff on 26-Jul-40. The new order eliminated the D-0/B designation, and instead introduced the D-2 sub-type, described as the variant that could be equipped with two external drop tanks, plus either bombs or a Dackelbauch, and only produced by Mtt Augsburg (M&P p.25). That meant the surviving D-0/Bs all now officially became D-2s since each of the D-0/Bs had indeed been converted from examples that had first been fitted with a Dackelbauch. (An accidental bureaucratic irony given that Erpr.Gr. 210 would next receive the D-3 sub-type, to which it was possible to attach drop tanks and bombs but never a Dackelbauch.)

Consequently when LP 18/3 of 1-Nov-40 reported deliveries of the D-series from Messerschmitt - all now completed - these did not mention the D-0/B at all but instead these were presented as:
83 D 0
52 D 2
21 D 2 with DB 601 N
6 D 3
10 D 3 with DB 601 N
6 D 4 (initially designated as the D-1)
Breaking these totals back to individual identities leads to the conclusion that - in accordance with the criteria for the new D-2 variant - the D-0/Bs were indeed now included within the total count of 52 D 2s, and also that it was more likely that there were 14 of these D-0/Bs rather than the 15 listed in M&P. (The latter point is not definitive at this stage since there are still gaps amongst the individual identities; just that on balance 14 does appear the rather more likely D-0/B total.)

In similar fashion the D-0/R1 & /R2 (Rüstzustände I & II) sub-variants (M&P pp.180/1) were now combined together here in the D 0 total of 83, the split most likely being 33 to 50 in accordance with the General Staff instruction of 25-Jun-40 that required two out of five to be fitted with a Dackelbauch (M&P p.22). (R I & II indicated respectively delivered fitted with and without a Dackelbauch. So the reality is that there were only just enough of Rüstzustand I to equip I./ZG 76, and - as beautifully evidenced now in 'Zerstörer' at p.120 - one of those Rüstzustand I examples was sent to ZG 2 in error.)

Entirely understood though that one would not expect to find this level of detail in a combat history.