You don't understand the startdates?
Take, for example, 19990426.1121
Let me stick some spaces in some helpful places:
1999 04 26 . 11 21
That better?
19990426 means 26th April 1999, and 1121 is in 24-hour clock format, IE 11:21AM
Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how Stardates work.