Members of the institutions, officials and other servants of the Union of any nationality, including former members, former officials and former other servants, who entered the service of the Union before the end of the transition period and who reside in the United Kingdom, as well as, irrespective of their nationality, spouses not separately engaged in a gainful occupation and children who are dependent on and in the care of such members, officials or other servants, shall be exempted from obligatory affiliation to and payment into national social security systems in the United Kingdom, under the same conditions as were applicable on the last day of the transition period, provided that the persons concerned are affiliated to the social security scheme of the Union.