As it stands now, it looks like everyone in range is affected by the beacon. It seems to provide an 8 second countdown on the buff that renews every 4 seconds. So if you go out of range, the effect stays active until that 8 second timer finishes running down. When you enter the range, the effect doesn't apply immediately, but rather comes on the next 4 second 'pulse' from the beacon.
Last edited by Irimar; 17th August 2012 at 02:39 AM.