I heard from my sis just recently, regarding crew mergers and
all that. Some ships were left in the port or somfin. Out of
service? Overhauling? Also partly cause of the ship they lost a few
years back, the one that got owned by a bigger ship. :/
Not unusual, the PV/APVs like Daring are used so often, they wear
out rather quickly. It is not unusual for one to stop at Changi
although based at Tuas because of engine failure/navigational
system failure and so on.
In an extreme case, I recall RSS Gallant had to be towed to
Changi after losing both engines.
The one they lost was Courageous, it's now sitting at my
base.