What would be gained by implementing a DMP on the OIDB service already in production since 2015? Never too late for the DMP?

The aim of this poster is to highlight the gap between a formal data management plan and the practical approach applied to an already launched service . The analysis focusses on the main topics of the DMP and identifies how to solve or improve main issues given the help of a datawarehouse under construction.  The candidate project 'OiDB' operates since mid-2015 and provides a data portal dedicated to the optical interferometry domain.
It collects observation logs or science ready files from several data repositories and facilities. The specifications of the project have been led by the associated scientific community in the Virtual Observatory framework. Many issues concerning the meta data have been discussed at the beginning of the project but no formal data management plan has been built. Let's try to complete a data management plan just now and see if it will point out any new issues. Are there any questions we should have asked before or any concerns we missed? The poster will report some feedback on the evolution of the data management process  from a practical point of view. It will show if these evolutions could have been anticipated if we have had a DMP at the very beginning of the project. This analyse will help the enhancement of the Grenoble Observatory's datacenter (OSUG-DC)  by pointing the priorities for new services such as data preservation or data identification.