I just came across the issue that I had a combobox with values taken from a "formula item".
But: the values didn't refresh on a partial refresh. I found that in the script editor for "values -> formula item" there is no choice between "compute dynamically" and "compute on page load". So I guess it's hard-wired to "compute on page load", which explains why the values don't compute again on a partial refresh.
Remember two things:
(1) the prefix "#" means "compute dynamically, "$" means "compute on page load"
(2) the source view is your friend if you miss some switch or property in some editor
You are my HERO!
If any of you out there will ever want to create a comboboxes on the repeater, with choices dependent on the repeater variable, this is what you are looking for!