Well, that's because you looked at BNDEP from the 'wrong'
direction. Looking at BNDEP from Bedok North Ave 4 may imply that
BNDEP looked small compared to the size of AMDEP and HGDEP. Try to
look at it from Simei Ave, at the T-junction of Simei St 3. From
there, you could see that BNDEP stretches deeper and is bigger than
what you've seen along Bedok North Ave 4.
Many new buses of BNDEP as well as those which will be retired were
also seen parked at this section of BNDEP. A good example of the
new buses are the 94XX VOs. I've even spotted a Trident at this
section of BNDEP a few weeks before the bus was launched.
Cheers and warm regards