SBST wont apply more trips, frequency need 1 DD only leh. if sbsT
applys more trips, ok.
Some food for thought for you:
More trips does not necessarily mean more buses, it can just
mean a repositioning of buses from one point to another, in this
case they just have to ensure there are buses running on the sector
with more demand (113A).
Wouldn't it make more sense to place a DD on another route which
requires it more than 113?
And logically speaking, why would you want to have a DD coming
less frequently than a SD coming more frequently?