can't change label colour on a just part of a clip

Hi, I'm having this issue:

If I change the color of a clip label in the timeline it now changes the color of every clip with the same name. Meaning, if I've cut up a video file to use in various parts of the timeline, now they all change. I used to use this as a quick way to know clips a client didn't like etc to change/replace (label a single clip red, for instance), and now I can't do that. (previously posted by codys72658089 but also my exact issue, in a previous version of PP)

In 15.4.0 the option to uncheck the option to "display the project item name and lbel colour for all instances" in no longer in the preferences panel (or at least I can't find it.

Can anyone help? 

Thanks