I just found a bug while undoing.
I had a parameter assigned to dashboard link 1 of a clip, I then assigned that parameter to time instead. When I tried to undo the time assignment, the label that was originally given to dashboard 1 remained but greyed out and the parameter said "Link Unavailable" underneath it.
The parameter's dropdown menu had Dashboard highlighted yet there was no Dashboard control happening
Resetting the parameter (right click) restored the Dashboard assignment but it also changed the way the range brackets of the parameter were positioned to the default full range. So, no actual reset as such, more a mixture of reset and undo.