The runway must have a strip surrounding it which is generally obstacle free, to cover the eventuality of an aircraft leaving the paved surface. For 02/20 this strip is 140 metres each side of the runway centreline extending for 60 metres before the threshold (ie earliest point of landing) and beyond the end of the declared TORA/LDA. Additionally there needs to be a Runway End Safety Area (RESA) extending outward from the strip ends for a minimum of 90 M as a safety buffer to counter an accident involving an undershoot or overrun. Consequently most of the extension is in fact the 02 strip end and RESA.
Should be no impact on the ILS minima for 20.