The McCanns were made arguido(a) on 7th Sept 2007. Sr Amaral was given a DCM on or about 3rd Oct 2007 ceasing to be involved in the case as a consequence. The case was archived back end July 2008.
It is interesting , if Sr Amaral The Boogah Man had it all round his neck as you suggest, that the arguido status was not lifted earlier. Maybe those that followed had been indoctrinated?
I'm not sure that I understand your question, Alice. The investigation had to continue either towards charging one or more people or to archival, whoever was in charge. Arguido status isn't lifted on anyone until the end of the investigation phase.
The only exception to that appears to be someone questioned by the UK (for which I haven't seen a specific provision in the PPC). If it is true that arguido status was lifted, then I can only assume for the moment that it was a temporary arrangement to equate to the UK version of being questioned under caution.