Very curious. How many trips can a particular vehicle take a day? Cos they are not using bus lane.
Even if they cut queue and such, from pick up point (let’s say Changi Airport) to drop off point (let’s say blue wave hotel) takes at least one hour one way. Considering the time taken to pick up and drop off, it’s at least 3 hours round trip. So at most they can take about three round trips a day and this assumes pick up and drop off no tour or anything. If it’s a day tour to Malaysia, then it’s only one trip a day
So it might raise eye brows but I don’t know if it’s “suspicious”. What’s more maybe it’s different drivers.