(5) For the purposes of paragraph (4), where a body corporate registered outside the United  Kingdom, or a partnership established outside the United Kingdom, has an office in the United  Kingdom, the principal office of the body corporate or partnership is its principal office in the  United Kingdom.  (6) For the purposes of paragraph (4)(c), where the person is an aeroplane operator, the proper  address includes an address derived from information supplied by Eurocontrol( a ).  PART 3  Monitoring, reporting and verification (“MRV”) of aeroplane operator annual CO$_{2}$  emissions  CHAPTER 1  General  Applicability of MRV requirements  CHAPTER 2  Monitoring of aeroplane operator annual CO$_{2}$ emissions  Monitoring of CO$_{2}$ emissions: Eligibility of monitoring methods  14 ( a ) Eurocontrol is the intergovernmental body established by the International Convention Relating to Co-operation for the  Safety of Air Navigation of 13th December 1960 (the Eurocontrol Convention).  ( b ) Guidance material on eligibility of monitoring methods, and associated thresholds, is provided in the Environmental  Technical Manual (Doc 9501), Volume IV – Procedures for demonstrating compliance with the Carbon Offsetting and  Reduction Scheme for International Aviation (CORSIA) which is available from the ICAO website at www.icao.int. For a  hard copy contact the ICAO E-Commerce and Publications Sales Unit at International Civil Aviation Organisation (ICAO),  999 Robert-Bourassa Boulevard, Montreal, Quebec H3C 5H7, Canada (telephone +1 514-954-8219 and e-mail  sales@icao.int).  ( c )  OJ L 250, 30.9.2019, p.10.  22. —(1) An aeroplane operator must monitor and record its fuel use from international flights in  accordance with an eligible monitoring method set out in paragraphs (3) to (6) for the 2019-2020  period and paragraphs (7) to (12) for the 2021-2035 period, and approved by the Regulator.  (2) Following approval and issue of its Emissions Monitoring Plan in accordance with article 24,  an aeroplane operator must use the same eligible monitoring method for the entire compliance  period( b ).  2019-2020 period  (3) Where an aeroplane operator has, prior to this Order coming into force, accumulated any fuel  use during the period of 2019-2020 pursuant to article 3 of Commission Implementing Regulation  (EU) 2019/1603( c ), that fuel use data must be used for the purpose of this Order.  (4) An aeroplane operator with annual CO$_{2}$ emissions from international flights greater than or  equal to 500,000 tonnes must use a Fuel Use Monitoring Method set out in Schedule 2.  (5) An aeroplane operator with annual CO$_{2}$ emissions from international flights of less than  500,000 tonnes must use either a Fuel Use Monitoring Method or the CERT set out in Schedules 2  and 3, respectively.  (2) The requirements of this Part apply to a new entrant aeroplane operator from the year after it  meets the requirements in paragraph (1).  21. —(1) The requirements of this Part apply to an aeroplane operator that produces annual CO$_{2}$  emissions greater than 10,000 tonnes from the use of one or more aeroplanes with a maximum  certificated take-off mass greater than 5,700 kg conducting international flights. 