You don't need to list for multiple flights for the same day to the same destination. If you don't make it, your name will roll to the next or have the agent roll your name to the flight you want to try. You do not need to relist. It just complicates things by doing that and yes...it can be a pain when people don't understand how things work. On another note though, if you were going to try for different destinations just to get across the pond, then you should be listed for each flight, this helps with planning for catering, etc.