Steps to duplicate:
Create a dropdown and link to a field in the Sharepoint list that contains 4 items
Add a new entry to the Sharepoint list so it now contains 5 items (or whatever, the exact number does not matter)
Open the form in New mode or Edit mode
results: the new item does not show up
Open the form in Designer
results: the new items does not show
To get the item to show must Re-Publish the form!!!!!!
NOT the best way to keep up with users adding/removing items.
I ASSUME this is a BUG - as the from is supposed to be LINKED to the field it should update itself?