You don't understand the startdates?
Take, for example, 20260321.1948
Let me stick some spaces in some helpful places:
2026 03 21 . 19 48
That better?
20260321 means 21st March 2026, and 1948 is in 24-hour clock format, IE 7:48PM
Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how Stardates work.