Clive D.W. Feather wrote:
Northern Ireland would remain part of the UK, so remains on GMT/BST.
The BBC article was exploring the reverse possibility, i.e., that Scotland would stay on GMT/BST whereas the remaining UK would switch to CET/CEST.
The Republic of Ireland remains a separate country.
As it happens, an Oireachtas committee is considering a time zone change for the Republic of Ireland. Public comments are solicited, due 12 September at 15:00 IST. Please see: Quann J. Public asked for submissions over moving Ireland to CET time zone. Newstalk 2014-07-25. http://www.newstalk.ie/reader/47.301.341/28729/0/ Such a change should not require a new zone in the tz database, only changes to an existing zone. However, it could cause Northern Ireland to lean more to switching to CET/CEST, and this in turn could make matters more interesting for the Scots, who tend to be opposed to such a change.