In some projects the most current iterations are displaying in the dropdown selector box in a User Story and in some projects the most current one or two projects are not displaying.
This is because there were more than 5 iterations with a newer schedule date than "todays" date. Essentially the selector displays the next 5 dates after "todays" date and the previous 5 items before todays date from the list. If there are more than 5 iterations with newer schedule date than "todays" date, only the next 5 Iterations display.
This was a design decision made for performance considerations.