I may be wrong, but I believe the runway extension is being driven by Ryanair who require a bit extra to operate their B738s. Unfortunately I have heard that they only require 50m more so that is probably what the BAA will eventually provide, unless a sound business case is made for a longer extension.
However I have noticed that the new 34 localiser site is well North of the old one (about 300m) so there is hope for a decent extension yet.
Topbunk - The AOS (previously known as the ADN NDB) was scrapped years ago. Incidentally I have been told that the ILS is actually CAT2 capable but the A/F lighting needs upgrading to allow this.