The Legal Impacts of COVID-19 in the Travel, Tourism and Hospitality Industry

6 d) The 80/20 rule must be suspended by a rule of law and the EU gave already signs that it will do so; e) Even if there is no legal suspension to the rule, airline carriers can allege changing of circumstances ( rebus sic standibus clause) to temporarily and unilaterally change the contracts made with airports, as the slot allocation is contractual. References GREMMINGER, Michael (2006), Commercial Slot Allocation - A Competition policy perspective . HAYLEN, Andrew & BUTCHER, Louise (2017), Airport slots , Commons Library, Briefing Paper number CBP 488. IATA Worldwide Airport Slots - Fact Sheet (May 2019). PHEASANT, John & GILES, Matthew, Slot trading in the EU , Global Competition Review, consulted at https://www.hoganlovells.com/~/media/hogan- lovells/pdf/publication/slottradingjpheasantmgiles_pdf.pdf. CORDEIRO, A. Menezes (1987), Da alteração das circunstâncias , Separata dos Estudos em Memória do Prof. Doutor Paulo Cunha, Lisboa.