The Citizen Band (CB-27) users are governed by a list of countries created by the italian association Alfa Tango, similar to DXCC entity list (ARRL) for which radio amateurs are governed.
Currently, there are 352 divisions on the CB-27 list. Catalonia is not included in either of the two lists. Obviously these lists have been invented by these two associations, they are not official, they have not been created by any state or public administration and they are not protected by any law of radio amateurs and CB-27. Therefore, there should be no problem in including Catalonia or any other territory.
In the case of CB, users of this band can use any callsign, since it is a free band without a license, so any prefix can also be used. The prefix 714 corresponds to Catalonia followed by the letters CT that corresponds to the top-level Internet domain of Catalonia (the current domain .CAT is the top-level Internet domain for catalan language and catalan culture, but it is not territorial).
Catalonia is the new CB-27 division and was created in February 21, 2021
EquipmentTransceiver: SUPER STAR 360FMMicrophone: SADELTA Echo Master PlusAntenna: TAGRA 5/8 GP-27