picklist update

I have a form that contains a picklist element as defined below:

must  have  firstChoice
(
     displayname  =  "First Choice"
     type  =  picklist
     values  =  weekends[activeWeekend].label
)

As you can see, the values are populated by pulling from another form with a criteria. Here's the thing, this is exactly how I want it to work when the data is originally submitted. However, I've noticed that if I want to edit this info after it's been submitted, the same criteria is being applied. The problem is that the original values are no longer available, but I want them to be. Does this make sense?

Here's what I tried per a suggestion in another post as part of the on load, on edit action:

//save temporary the actual picklist value
tempFirstChoice = input.xfirstChoice.toString();
tempSecondChoice = input.secondChoice.toString();
for each r in weekends  [activeWeekend]
{
    xfirstChoice:ui.add(r.label);
    secondChoice:ui.add(r.label);
}
//write back the temporary saved picklist value
input.xfirstChoice = tempFirstChoice;
input.secondChoice = tempSecondChoice;

This doesn't seem to have worked though.