Actaully its not. In the time i was there i saw an average of 9 acklay a minute. My guildy was there 45 mins before me and saw thr same. If the event lasted 1 hour. (I believe ot lasted longer) but if only 1 hour thats 540 acklays in 1the hour.
Now 12 acklay spawn each day.
12 x 7 =84 x 4.3 wks in a month = 361 acklay a month.
So at least 1.5 months worth of acklay. Possibly 3 months worth if the event was 2 hours.