You can create yourself a colour file that shows only the reference names, also a macro to include the colour file that will do the change.
So in fact it is then only a 1 second operation.
I think the problem may stem from your moving the reference names off of the original layer that they were defined in the library. Perhaps it is recognising that you did this, thinking that you did this for a good reason it is not changing them back because it would then perhaps upset you. I know it would upset me if it continually put them back on the default layer after I had spent so much time moving them all.
So perhaps its not so much a bug as an intended part of the relevant feature, admittedly it may need a tick box/selection to "reset attribute layers".
IMO it is not one more step in the design process, we define what layer the refnames go on in the library, this is the default way of doing it in Cadstar.
You have just done something different & now expect the update to change it back for you.
If you want your refnames on a different layer then either change them in the library, add different named origins on different layers & use the report file method, or just change them as advised.
IMO its not a bug, a bug is a feature that does not work. This feature does work its just that it does not cater for what you are wanting it to do.