It's not only GA that would be affected by the closure of 21/03. With the main runway 31/13 being regularly affected by crosswinds the loss of the secondary runway could result in diversions or cancellations of Ryanair scheduled services - indeed it might result in Ryanair reconsidering their whole operation. Incidentally with a gale blowing straight down 21 I have seen it used by no less than 747 freighters and a C-5 Galaxy.