Hold until relieved -- I mean released

Sadly perhaps, we have this interesting item from Nigeria reported by Punch (Nigeria).

A seaman, Nyeke Lucky, is presently languishing in a prison of the Nigerian Navy, Quorra, in the Apapa area of Lagos State, three months after his term has ended.

Interestingly this has happened in the U.S. due to an administrative error within the confinement facility, but, usually for only a few days And in some cases there is litigation to enforce the release of the detained person where commanders have sought to keep servicemembers in confinement in possible defiance of judicial orders.  I'm thinking of cases such as Frage v. Moriarty, 27 M.J. 341 (C.A.A.F. 1988).  And then there's the current Coast Guard case of Cooley.

In response to his lawyer's request the Navy apparently

“The judgment passed on Lucky was awaiting the confirmation of the Chief of Naval Staff before he would serve the term, but he had served it already. I have also written the naval authorities and sued them for extending his jail term.

Calling all cars, Ooops, I mean all Nigerian military lawyers.  This procedure seems odd.  Is it the law in Nigerian military cases that the person doesn't begin their confinement until what we in the U.S. call the convening authority (CA) action?  Or is it that there is no credit for confinement served prior to the CA action?