If you Google "Knock airport development plan pdf", and download the first link that comes up you will see the general proposals.
Page 65 shows the proposals for the terminal building itself. It's basically a major expansion of the apron to make space for a passenger boarding bridge, serving a (frankly excessive) 15 aircraft stands, as well as an additional taxiway to the runway. Would require significant investment, including relocation of the fuel bunds and major earthworks.