Click on item to see modal panel with item details. The difference between two shedules is that one shows modal panel after ajax event, which rerenders modal panel, and the other does so after before ajax update. In the second case you may see that modal panel appears, old data are still there and then, blink, and new data show up. Length of that lag depends on your connection speed.
To cope with such behaviour, shedule is equipped with xxxComplete callbacks that are called when ajax requests finish and all components on the page have been re-rendered. This works, of course, only in ajax mode.