Yesterday 4 sv 858 A22s bunching and departing at same time from Airport Boulevard towards Changi Airport terminal 3.
Wonder what the headway will be before the first A22 comes. Given sv 858 is at an average frequency of 07-08 mins, this means that there will be a gap of 28-30 minutes from CGA itself. By the time the bus comes to Yishun, not sure how many more 858 buses will bunch, unless the A22s help each other by skipping stops to close the gap.