What happens if a French citizen does an international transit in Narita International Airport (NRT) but their outbound flight is canceled?

Question

IATA states for Japan:

14. Passengers transiting through Tokyo (NRT) must transit on the same calendar day.

What happens if a French citizen does an international transit in Narita International Airport (NRT) but their outbound flight is canceled? (outbound flight = the flight from NRT to outside Japan) Would they be allowed to stay somewhere overnight, and if so, where? Would they have to try to fly somewhere else, assuming that there are still some flights leaving before midnight? etc.

Assume:

• the French citizen has no tie and no visa/paperwork with Japan.
• international transit in Narita International Airport (NRT) means that the route is: outside Japan -> NRT -> outside Japan.

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Full IATA information about Japan:

Japan Published 06.08.2020

1. Passengers who have transited through or have been in Afghanistan, Albania, Algeria, Andorra, Antigua and Barbuda, Argentina, Armenia, Australia, Austria, Azerbaijan, Bahamas, Bahrain, Bangladesh, Barbados, Belarus, Belgium, Bolivia, Bosnia and Herzegovina, Botswana, Brazil, Brunei Darussalam, Bulgaria, Cameroon, Canada, Cape Verde, Central African Rep., Chile, China (People's Rep.), Chinese Taipei, Comoros, Congo, Congo (Dem. Rep.), Colombia, Costa Rica, Cote d'Ivoire, Croatia, Cuba, Cyprus, Czechia, Denmark, Djibouti, Dominica, Dominican Rep., Ecuador, Egypt, El Salvador, Equatorial Guinea, Estonia, Eswatini, Finland, France, Gabon, Georgia, Germany, Ghana, Greece, Grenada, Guatemala, Guinea, Guinea-Bissau, Guyana, Haiti, Honduras, Hong Kong (SAR China), Hungary, Iceland, India, Indonesia, Iran, Iraq, Ireland (Rep.), Israel, Italy, Jamaica, Kazakhstan, Kenya, Korea (Rep.), Kosovo (Rep.), Kuwait, Kyrgyzstan, Latvia, Lebanon, Liberia, Libya, Liechtenstein, Lithuania, Luxembourg, Madagascar, Macao (SAR China), Malaysia, Maldives, Malta, Mauritania, Mauritius, Mexico, Moldova (Rep.), Monaco, Montenegro, Morocco, Namibia, Nepal, Netherlands, New Zealand, Nicaragua, North Macedonia (Rep.), Norway, Oman, Pakistan, Palestinian Territory, Panama, Paraguay, Peru, Philippines, Poland, Portugal, Qatar, Romania, Russian Fed., San Marino, Sao Tome and Principe, Saudi Arabia, Senegal, Serbia, Sierra Leone, Singapore, Slovakia, Slovenia, Somalia, South Africa, Spain, St. Kitts and Nevis, St. Vincent and the Grenadines, Sudan, Suriname, Sweden, Switzerland, Tajikistan, Thailand, Turkey, Uruguay, USA, Ukraine, United Arab Emirates, United Kingdom, Uzbekistan, Vatican City (Holy See), Venezuela or Viet Nam in the past 14 days are not allowed to enter. -This does not apply to:

• nationals of Japan;
• spouses or children of nationals of Japan if they can prove it;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission by 2 April 2020;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission between 3 April and 28 April 2020 and have only been in Afghanistan, Algeria, Antigua and Barbuda, Argentina, Azerbaijan, Bahamas, Bangladesh, Barbados, Belarus, Botswana, Cameroon, Cape Verde, Central African Rep., Colombia, Comoros, Congo, Costa Rica, Cuba, Djibouti, Dominican Rep., El Salvador, Equatorial Guinea, Eswatini, Gabon, Georgia, Ghana, Grenada, Guatemala, Guinea, Guinea-Bissau, Guyana, Haiti, Honduras, India, Iraq, Jamaica, Kazakhstan, Kenya, Kuwait, Kyrgyzstan, Lebanon, Liberia, Libya, Madagascar, Maldives, Mauritania, Mexico, Namibia, Nepal, Nicaragua, Oman, Pakistan, Palestinian Territory, Paraguay, Peru, Qatar, Russian Fed., Sao Tome and Principe, Saudi Arabia, Senegal, Sierra Leone, Somalia, South Africa, St. Kitts and Nevis, St. Vincent and the Grenadines, Sudan, Tajikistan, Ukraine, United Arab Emirates, Uruguay, Uzbekistan or Venezuela;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission between 29 April and 15 May 2020 and have only been in Afghanistan, Algeria, Argentina, Azerbaijan, Bahamas, Bangladesh, Botswana, Cameroon, Cape Verde, Central African Rep., Colombia, Comoros, Congo, Costa Rica, Cuba, El Salvador, Equatorial Guinea, Eswatini, Gabon, Georgia, Ghana, Grenada, Guatemala, Guinea, Guinea-Bissau, Guyana, Haiti, Honduras, India, Iraq, Jamaica, Kazakhstan, Kenya, Kyrgyzstan, Lebanon, Liberia, Libya, Madagascar, Maldives, Mauritania, Mexico, Namibia, Nepal, Nicaragua, Pakistan, Palestinian Territory, Paraguay, Sao Tome and Principe, Senegal, Sierra Leone, Somalia, South Africa, St. Vincent and the Grenadines, Sudan, Tajikistan, Uruguay, Uzbekistan or Venezuela;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission between 16 May and 26 May 2020 and have only been in Afghanistan, Algeria, Argentina, Bangladesh, Botswana, Cameroon, Central African Rep., Comoros, Congo, Costa Rica, Cuba, El Salvador, Eswatini, Georgia, Ghana, Grenada, Guatemala, Guinea, Guyana, Haiti, India, Iraq, Jamaica, Kenya, Kyrgyzstan, Lebanon, Liberia, Libya, Madagascar, Mauritania, Namibia, Nepal, Nicaragua, Pakistan, Palestinian Territory, Paraguay, Senegal, Sierra Leone, Somalia, South Africa, St. Vincent and the Grenadines, Sudan, Tajikistan, Uzbekistan or Venezuela;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission between 27 May and 30 June 2020 and have only been in Algeria, Botswana, Cameroon, Central African Rep., Comoros, Congo, Costa Rica, Cuba, Eswatini, Georgia, Grenada, Guatemala, Guyana, Haiti, Iraq, Jamaica, Kenya, Lebanon, Liberia, Libya, Madagascar, Mauritania, Namibia, Nepal, Nicaragua, Palestinian Territory, Paraguay, Senegal, Sierra Leone, Somalia, St. Vincent and the Grenadines, Sudan, Uzbekistan or Venezuela;
• residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident", who have departed Japan with Re-entry Permission between 1 July and 23 July 2020 and have only been in Botswana, Comoros, Congo, Kenya, Liberia, Libya, Madagascar, Namibia, Nepal, Palestinian Territory, Paraguay, Sierra Leone, Somalia, Sudan, Suriname, Uzbekistan or Venezuela;
• passengers with a Special Permanent Residence Permit. However, they must have a Re-entry Permit from a regional immigration officer;
• US military personnel;
• civilian personnel of the US armed forces in Japan and their dependents;
• nationals of Thailand residing in Thailand and arriving directly from Thailand. They must have a visa issued by Japan with "EX" in the Remarks column or have the Letter of Confirmation of Submitting Required Documentation for Re-entry into Japan. They must also have a medical certificate with a negative Coronavirus (COVID-19) test result issued at most 72 hours before departure;
• nationals of Viet Nam residing in Viet Nam and arriving directly from Viet Nam. They must have a visa issued by Japan with "EX" in the Remarks column or have the Letter of Confirmation of Submitting Required Documentation for Re-entry into Japan. They must also have a medical certificate with a negative Coronavirus (COVID-19) test result issued at most 72 hours before departure;
• residents of Japan with the Letter of Confirmation of Submitting Necessary Documentation for Re-entry into Japan, and with a medical certificate with a negative Coronavirus (COVID-19) test result issued at most 72 hours before departure.

2. A completed "Quarantine Questionnaire" must be presented upon arrival.
3. Passengers and airline crew are subject to medical screening.
4. Visa exemption for passengers with passengers with a British passport, Hong Kong (SAR China) passport, Macao (SAR China) passport is suspended.
5. Visa exemption for nationals of Andorra, Argentina, Austria, Bahamas, Barbados, Belgium, Brunei Darussalam, Bulgaria, Costa Rica, Croatia, Czechia, Cyprus, Denmark, Dominican Rep., El Salvador, Estonia, Finland, France, Germany, Greece, Guatemala, Honduras, Hungary, Iceland, Indonesia, Iran, Ireland (Rep.), Israel, Italy, Korea (Rep.), Latvia, Lesotho, Liechtenstein, Lithuania, Luxembourg, Malaysia, Malta, Mexico, Monaco, Netherlands, Norway, Peru, Poland, Portugal, Romania, San Marino, Singapore, Slovakia, Slovenia, Spain, Suriname, Sweden, Switzerland, Thailand, Tunisia, United Arab Emirates, Uruguay and Vatican City (Holy See) is suspended.
6. Visa exemption for nationals of Azerbaijan, Bangladesh, Cambodia, Colombia, Georgia, India, Kazakhstan, Lao People's Dem. Rep., Mongolia, Myanmar, Nauru, Oman, Pakistan, Palau, Papua New Guinea, Paraguay, Qatar, Samoa, Solomon Isl., Turkmenistan, Ukraine, Uzbekistan and Viet Nam with a diplomatic, official or service passport is suspended.
7. Visa exemption granted to passengers with an APEC Business Travel Card issued by Brunei Darussalam, China (People's Rep.), Hong Kong (SAR China), Indonesia, Korea (Rep.), Malaysia, Mexico, Papua New Guinea, Peru, Philippines, Russian Fed., Singapore, Thailand or Viet Nam, is suspended.
8. Nationals of China (People's Rep.) with a passport issued in Hubei Province or Zhejiang Province (China People's Rep.) are not allowed to enter Japan.

• This does not apply when passengers can prove that they have not been in Hubei Province and Zhejiang Province the last 14 days.

9. Passengers who were in the cruise ship 'Westerdam' are not allowed to enter Japan. - This does not apply to nationals of Japan.
10. Visas issued on or before 8 March 2020 by the Embassies, Consulates-General and Consulate of Japan in China (People's Rep.), Hong Kong (SAR China), Korea (Rep.) or Macao (SAR China) are invalidated.
11. Visas issued on or before 20 March 2020 by the Embassies, Consulates-General and Consulate of Japan in Andorra, Austria, Belgium, Bulgaria, Croatia, Czechia, Cyprus, Denmark, Egypt, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Iran, Ireland (Rep.), Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, Netherlands, Norway, Poland, Portugal, Romania, San Marino, Slovakia, Slovenia, Spain, Sweden, Switzerland, United Kingdom or Vatican City (Holy See) are invalidated.
12. Visas issued on or before 27 March 2020 by the Embassies, Consulates-General and Consulate of Japan in Bahrain, Brunei Darussalam, Congo (Dem. Rep.), Indonesia, Israel, Malaysia, Philippines, Qatar, Singapore, Thailand or Viet Nam are invalidated.
13. Visas issued on or before 2 April 2020 by the Embassies, Consulates-General and Consulate of Japan in Afghanistan, Algeria, Angola, Antigua and Barbuda, Argentina, Azerbaijan, Bahamas, Bangladesh, Barbados, Belarus, Belize, Benin, Bhutan, Botswana, Burkina Faso, Burundi, Cambodia, Cameroon, Cape Verde, Central African Rep., Chad, Colombia, Comoros, Congo, Cook Isl., Costa Rica, Cuba, Djibouti, Dominican Rep., El Salvador, Equatorial Guinea, Eritrea, Eswatini (Swaziland), Ethiopia, Fiji, Gabon, Gambia, Georgia, Ghana, Grenada, Guatemala, Guinea, Guinea-Bissau, Guyana, Haiti, Honduras, India, Iraq, Jamaica, Jordan, Kazakhstan, Kenya, Kiribati, Kyrgyzstan, Kuwait, Lao People's Dem. Rep., Lebanon, Lesotho, Liberia, Libya, Madagascar, Malawi, Maldives, Mali, Marshall Isl., Mauritania, Mexico, Micronesia (Federated States), Mongolia, Mozambique, Myanmar, Namibia, Nauru, Nepal, Nicaragua, Niger, Nigeria, Niue, Oman, Pakistan, Palau, Palestinian Territory, Papua New Guinea, Paraguay, Peru, Russian Fed., Rwanda, Samoa, Sao Tome and Principe, Saudi Arabia, Senegal, Seychelles , Sierra Leone, Solomon Isl., Somalia, South Africa, South Sudan, Sri Lanka, St. Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Sudan, Suriname, Syria, Tajikistan, Tanzania, Timor-Leste, Togo, Tonga, Trinidad and Tobago, Tunisia, Turkmenistan, Tuvalu, Uganda, Ukraine, United Arab Emirates, Uruguay, Uzbekistan, Vanuatu, Venezuela, Yemen, Zambia or Zimbabwe are invalidated.
14. Passengers transiting through Tokyo (NRT) must transit on the same calendar day.
15. Effective 7 August 2020, residents of Japan with “Permanent Resident", "Spouse or Child of Japanese National", "Spouse or Child of Permanent Resident" or "Long Term Resident" who have been in Bangladesh, Pakistan, Philippines or Peru in the past 14 days must have:

• the Letter of Confirmation of Submitting Necessary Documentation for Re-entry into Japan, and
• a medical certificate with a negative Coronavirus (COVID-19) test result issued at most 72 hours before departure.

Answer 1

If your connecting flight is cancelled before you depart for NRT, the airline will update your itinerary, and you have the right to insist on a new itinerary, potentially through a different connecting airport, that is valid in terms of visas, COVID entry requirements etc. (That said, if they can't find one, the airline also has the right to cancel your itinerary entirely and refund you the money.)

If your connecting flight is cancelled after you're already on your way, the same will happen, only there will be less options because you're already at NRT and they may not be able to find an option that departs on the same day.

If you need to stay overnight, the airline will liaise with Japanese authorities. In normal times, French citizens could simply enter Japan for up to 90 days; for other nationalities, they would likely grant a Shore Pass valid up to 72 hours that will let you leave the airport freely. However, thanks to COVID, you're more likely to end up in a quarantine facility of some sort (which may well be a hotel near the airport). Nevertheless, you're not going to be detained or sent back, and the airline should cover the cost of accommodation and meals because this was their fault.