If you look at the figures in the link they are only scheduling 62 in 2 hours (an average of 31) but 34 in the first hour and 28 in the second hour. So it appears they are over scheduling one hour and that 3 aircraft from that first hour will not get away and incur delay (but only of up to 6 minutes), then under scheduling the next hour so that the schedule as a whole gets back on track by the end of the second hour.
I can't decide if this is rather dumb or very clever..!!
34 is therefore seems to be a false number for runway capacity but a valid one for scheduling.