Agree, it looks like your booking reference #.

Usually when booking a ticket online, an airline's site offers a link to their page called "Fare Conditions"

On that page, you would find the Fare Basis Code and all of the rules and conditions associated with that fare.

On EF, each of the fare basis codes reflect different cabins and fare types and each one has the fare conditions associated with it. Some require 7 day advance purchase, some might require a Sunday stay and so on.

There are also fare basis codes that are not shown and those may be associated with a third party travel agency-type group booking.


OP - did you book your ticket on the CX website or with a travel agent or OTA?