The decision to build the intermediate night fighter was decided on September 1, 1944 at a meeting in the Messerschmitt design office with partisipation of RLM and Messerschmitt. At a meeting in mid-September 1944 where DHL, RLM and Messerschmitt participated it was agreed that DHL should build the night fighter. Messerschmitt design office supplied the design documents to DHL on September 28, 1944. At a meeting held at DHL on October 14, 1944 the mock-up of the cockpit was discussed and it was decided that DHL should engineer the changes to the rear fuselage to accommodate the standard 600 l fuel tank from the single seated version. So the only component in common between the trainer and the night fighter was the 400 l fuel tank under the rear cockpit replacing the standard 900 l fuel tank.
DHL was ONLY making night fighters from single seated aircrafts. It was discussed in March 1945 that DHL should shift the production to only making night fighters and no trainers. This was not carried out.
In the meantime Messerschmitt design office was working on the series version of the night fighter(with a stretched fuselage), suppling the design drawings and documents on December 22, 1945. This version was probably only build as one prototype that was destroyed in a bombing raid in March 1945.
Messerschmitt design office supplied a similar design package to Blohm & Voss in the early summer 1944 for the trainer version.
Blohm & Voss was also producing complete tail sections for the ME 262.