You don't understand the startdates?
Take, for example, 20250514.1831
Let me stick some spaces in some helpful places:
2025 05 14 . 18 31
That better?
20250514 means 14th May 2025, and 1831 is in 24-hour clock format, IE 6:31PM
Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how Stardates work.