From the North Wales Weekly News (Nov. 10, 2011):
Plas Dulas, which dates back to the 1780s, will make way for a housing development following a unanimous decision by Conwy County Council planners yesterday.
Developer Alex Davies was granted permission to build 15 detached two storey buildings and a children’s play area on the site.
The demolition of Plas Dulas had been threatened for many months, but this decision appears to be final and to signal the end of the effort by some heritage organizations to preserve the property.
(known as Arnold House when Evelyn Waugh taught there in the 1920s) inspired Llanabba Castle in Decline and Fall.
A photographic tour of the property taken in Feb. 2011 can be viewed here.
Update (Dec. 14th): Commenter Duncan McLaren offers the following correction: "Evelyn Waugh did have a connection with Plas Dulas in 1925. But Arnold House, the much more significant building in his biography, where Waugh taught and lodged, is located further up the hill of Llanddulas."