You don't understand the startdates?
Take, for example, 20180310.1341
Let me stick some spaces in some helpful places:
2018 03 10 . 13 41
That better?
20180310 means 10th March 2018, and 1341 is in 24-hour clock format, IE 1:41PM
Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how Stardates work.