I have followed my 3rd option:
With a Dynamo Graph I am able to copy the values in a parameter, remove it, create it again and feed it. I use a “dummy” value (e.g.: 999) which is removed, and only “real” data is than copied to the new parameter.
The only problem I’ve found is that the parameter will disappear from all schedules, and I haven’t developed a solution for that.