Guido: From all that we've seen of Prester's Exile, it's actually far too small to accommodate all of Prester's population. In all likelihood it only took a small fraction (those willing to take the risk on the first trip, and its military Vanguard of two Claim-Solais type battleships), while the rest stayed behind to oversee Prester. Indeed, from Tatiana's comments to her uncle in Hourglass, this is exactly what happened. Silver Wing however hints that the Anatoray-Disith Exile has been making multiple trips, so who knows now how much of Prester's population has returned since then?
I do respect your opinions, but let me give you a word of advice. Don't take for granted that all the people using this forums have knowledge about absolutely everything in anime, manga, light novels, and visual/audio games.
I do know that there is a Last Exile manga out there, but that's my knowledge about it; neither have read it nor I know where to find it.
For Last Exile my knowledge is restricted exclusively to the first and the current anime seasons.