“The Court of Justice takes formal notice of the fact that the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the EU has the effect of bringing to an end the mandates of the British Members of the Institution with effect from 31 January 2020 at midnight. The number of Judges of the Court of Justice and of the General Court, fixed at one for each Member State for the Court of Justice and two for each Member State for the General Court, is therefore reduced with immediate effect at the time of the UK’s withdrawal from the EU. On the other hand, in accordance with the declaration of the Conference of the Representatives of the Governments of the Member States of 29 January 2020 on the consequences of the UK’s withdrawal from the EU for the Advocates General of the Court of Justice, the number of Advocates General of the Court of Justice, fixed at eleven by the Council Decision of 25 June 2013, is not affected by that withdrawal. Pending the nomination of a new Advocate General by the governments of the Member States, Ms Eleanor Sharpston will continue to hold office, in accordance with Articles 5 and 8 of the Statute of the Court of Justice, until her successor takes up his or her duties. In accordance with the terms of the withdrawal agreement, the Court of Justice is to continue to have jurisdiction in any proceedings brought by or against the UK before the end of the transition period, which is set as 31 December 2020. It is also to continue to have jurisdiction to give preliminary rulings on requests from courts and tribunals of the UK made before the end of the transition period.The Court of Justice pays tribute to the major contribution of all its former British members to European integration in general and to the case-law of the Court of Justice and the General Court in particular”.
from https://curia.europa.eu/jcms/jcms/p1_2806590/en/