According to the CJEU summary:

In a procedure to transfer an asylum seeker, in order to ensure the effectiveness of Article 20(1)(d) and Article 20(2) of Regulation No 343/2003 establishing the criteria and mechanisms for determining the Member State responsible for examining an asylum application lodged in one of the Member States by a third-country national, that article must be interpreted as meaning that, where the legislation of the requesting Member State provides for suspensive effect of an appeal, the period for implementation of the transfer begins to run, not as from the time of the provisional judicial decision suspending the implementation of the transfer procedure, but only as from the time of the judicial decision which rules on the merits of the procedure and which is no longer such as to prevent its implementation. In the light of the objective pursued by setting a period for the Member States, the start of that period should be determined in such a manner as to allow the Member States a six-month period which they are deemed to require in full in order to determine the practical details for carrying out the transfer.