Officer filed tickets 9 almost 10 months after the incident. How and Why?

My Fiance was pulled over in early March 2024. She dropped her phone and swerved reaching for it. Officer gave her field sobriety, breathalyzer, and wanted blood test. She passed breathalyzer, and Field, but messed up being honest with officer about consuming Marijuana earlier that day, he gave her a DUI as well as a slew of other tickets. He never filed these with the court, only the automatic Ding! That gets sent to the Department of Revenue/Department of Transportation is what she had to deal with the last 10 Months. (AUTO suspends tour lisence for a year, puts you on the list to have to complete an evaluation and SATOP class)(substance abuse traffic offenders program). All of which she has completed.

We just checked CaseNet and looks like the officer filed the tickets finally and officially with the court. Why would he wait so long to do so? Is the judge going to wonder why the officer waited almost a year before filing the tickets, and won't that play somewhat into the case?

I don't want to say we thought she got super lucky, but it was almost getting to the point we figured the officer may not ever file these tickets, so now we are just wondering obviously he can wait this long, because he did. But does anyone know why an officer would do such a thing and make someone's life even more burdened by these charges?