Actually, I think such plan may be extended to a later
date.
The reason why ARBP is there is because it serves a strategic
location for buses of nearby interchanges to park. (for e.g.
Clementi Int, Buona Vista Terminal, Harbourfront, Marina Centre) If
ARBP is to be removed, buses of the mentioned
terminals/interchanges may have to shift all the way up to Bukit
Batok Depot, which means longer travelling time for the buses to
travel from depot interchange.