The Police Reports are the Police Reports. One of the very few things we have from LE. In the last 48 years I have never heard one person say the police reports were wrong.
It would not count as wrong by any means to have the timing bit off.
And there is a big hint that there is some freedom with timing taken cause filing MP report it's not something that anyone can complete in 5 or even 10 minutes (especially while everything has to be written by hand).
Of course everyone has different speed of writing, some are faster, some slower, but filing such report requires that a conversation is happening with the person filing the report - could be just quick question, quick answer but that's bit less likely than having an officer asking like a two-three additional questions to get the best grasp on the info provided.
But it's absolutely impossible that the timing is completely accurate there. Cause it's impossible that exact same officer was able to get two MP reports from two different family members, one of which was physically at the location, one of which called.
It doesn't necessarily mean anything bad. Could be just the drill to not bother with time like 6:07 AM or 6:23 AM and using only times like 6:00 AM or 6:30 AM and so on. With the rule that anything completed even a minute after 6 AM is officially counted as filed at 6:30 AM, as well as something completed at 6:29 AM.
Let's say that DA insisted that it was 10:30 when she last saw Rachel. But the officer decided to make sure and asked her few additional questions. And it went like this:
She: ... and I think she left home around 10:30 AM.
Officer: So you're not sure?
She: No, I was sleeping then, she woke me up to ask me if I'll join her but I stayed in bed.
Officer: How do you know it was 10:30 then, have you looked at the clock? Did she said what time is it? Have you asked her what time is it?
Me: Well, no, but I think that she left and when I was falling back to sleep I heard the radio jingle before their hourly news, so it had to be half past 11 when I saw her... I think. Surely it was after 10:00 AM cause I got uo to pee and then I heard the time in the news clearly.
Officer: And when did you wake up?
She: Sometime after 3 PM.
Officer: So you're sure that it was past 10 AM but before 3 PM and definitely sometime before the hourly news in the radio. So it could be 10:30, 11:30, 12:30, 13:30 or even 14:30. Okay, so we have to narrow it down a bit, let's say it was 12:30.
It would not be wrong for him to put 12:30 there (Ideally he would elaborate in a way that it'd be clear that it could be basically every half-past-x-hour between 11 AM and 3 PM but it'd be crazy to expect that he had the time to be so specific with everything), he'd be absolutely right... but the timing still could be off.
Different story if, while filing the report she said
oh, I'm sure it was 12:30 cause I asked her what time is it, I looked at my watch and it was 12:30... and then changed her story and started insisting on 10:30.