Full day are usually those peak hr buses, same driver drive for
that day
Half day are those AM or PM shift one...
AM - They drive bus from depot to the starting pt started on the
timetable (Need not be Bus Int can be bus stop say along Clementi
Rd) till 2-3pm
PM - Starts from 2-3pm at bus interchange till 1900 - 0145
depending on the timetable again.. Drives back to depot