Last train should be the latest entrance time, because after entering directly board the bus, full-vehicle departure is as soon as possible. Inbound each scenic spot can get on and off at will, but once full vehicle must depart immediately.
During Qingming holiday, I went to somewhere and only got one ticket option. The bus schedule and ticket time were the same. I had my ID card scanned to enter the bus where tourists were already boarding ahead of me.
The last bus should be the latest arrival time at the park, as it enters directly onto the bus and leaves when full. Returning to each scenic spot is possible for boarding and alighting until the bus is full.
“Spent a trip during Qingming holidays, tickets can only choose one place at a time, sightseeing bus and ticket times are the same, swipe ID card to get on board, there were already tourists getting off when we got on.”