Look here to see where your current flotilla base is. Unfortunately the game does not always inform you when it has changed, and sometime when it does inform you, the change is not saved to your savegames leading you to go to the wrong place.
CareerTrack.upc in the savedgames folder (in C:\Documents and Settings\...\My Documents\SH4\data\cfg
Sort your saved games folders by date and look within the latest folder.
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