Bollards on maintenance / cycle track

Controversy over bollards is not new, but in recent weeks some of the bollards along the maintenance / cycle track have been changed.

It appears this has only been at the major road junctions, and only the centre of the three bollards has been changed. Some at the lesser crossings, just as dangerous, have not (yet?) been changed. 

At Milton Road junction

Note the old bollard remains in front of the new one. Both it, and the other 2 are lowered.

At Fendrayton Lakes - looking away from the junction towards Swavesey

Note the reflector is white.

Fendrayton Lakes - same bollard looking towards junction.

Note the reflector is red.

The bollards appear the same as the ones on the new busway extension to to Cambridge North station reported on this blog here,... except for the reflectors. There you will see not one, but three bollards with orange reflectors on both sides. The new ones have red reflectors one side and white the other.

Why this difference? Maybe(?) red means 'Danger' - you are approaching a junction, and white means you have left it.

Reflectors are designed to reflect light back in exactly to where it came from. For this reason - they are most effective for cyclists if their light is near their eyes - e.g. a head mounted light.
They are much less effective for cyclists with handlebar mounted lights - especially if their lights are thoughtfully dipped to prevent dazzling oncoming traffic.

However, there is a stud light just in front of the bollards, (I can't remember what colour), which does not rely on reflecting light from the cyclist.

But why only one new style bollard?
- maybe one is enough (and the others will be left down)?
- maybe to leave enough room for the Multihog to grit the track without having to stop so often?

Anybody have any more information on the reasons behind this change?