Yes, there were at least two military airlift versions, the STA (side-loading) and MTA (rear-loading with ramp). The COD design was I think related to the STA version with arrestor hook. The tanker variant I think was a newer conversion idea from 2013.
Details can probably be found on the Secretprojects website on all of these.
_________________ Hood's Worklist
English Electric Canberra FD
Interwar RN Capital Ships
Super-Darings
Never-Were British Aircraft