British emergency passport

British emergency passports (also known as Emergency Travel Documents (ETD)) are issued by British diplomatic posts to British nationals and unrepresented Commonwealth citizens for the purpose of urgent travel overseas with a maximum validity of one year.
Eligibility.
British nationals, as well as unrepresented Commonwealth citizens, who need to travel urgently and whose passport has expired, been lost or been stolen can be issued with a British emergency passport by a British foreign mission. However, for a British emergency passport to be issued to a non-British Commonwealth citizen, permission must first be obtained from the individual's home government.
Physical appearance.
The following information appears on the biodata page:
Use.
The emergency passport can be used to make a single or return journey to the UK or another country of residence, via a maximum of five transit countries.
The emergency passport is issued with a validity which is limited to the shortest time appropriate to the holder’s travel requirements whilst taking account of the transit and destination country requirements (for example, many countries require travel documents to have a minimum validity of six months).
Providing an itinerary.
The Foreign and Commonwealth Office state that on applying for an Emergency Travel Document "You will be asked to provide an itinerary for your journey". However 'providing an itinerary' is not the same as 'booking a ticket' and if a passport has been reported lost or stolen using LS01 the applicant will have completed a declaration "I understand that completing and returning this form will result in the related passport being cancelled, that it may never be used again" which would appear to indicate that the number of the lost/stolen passport cannot be used to book any tickets.