Ofcom have issued guidance about their policy on temporary call signs and call sign enhancement

The guidance is particularly noteworthy because this is possibly the first time Ofcom (or their predecessors) have used the correct term British Islands (Interpretation Act 1978). Previously Ofcom had incorrectly used "United Kingdom" to refer to the UK and the Crown Dependencies.

Radio amateurs had pointed out to Ofcom that the Ministry of Justice had stated: "Government officials must never state or imply that the Crown Dependencies are part of the United Kingdom, or Great Britain or England or act on that assumption."

Ofcom Call Sign Guidance - http://licensing.ofcom.org.uk/radiocommunication-licences/amateur-radio/guidance-for-licensees/policy-temp-call-signs-enhancement/