How to increase the nmea logging period

Hi experts,

I got an Ultra2 a while ago and has been using it on walking / running exercise.

Recently I came across to this apple site: debug profile and I'm curious about what I would get during the exercise.

So I follow the instruction and install the location services profile. After getting the sysdiagnose report, I try to get location related information from it. And it seems that the log from "locationd" and "gpsd" are what I'm looking for.

But when I try to look into the nmea information, I found out the sysdiagnose only provide around 10-15 mins of nmea data.

For example, let's say I have a walking exercise from 0900 - 1000, but I can only see nmea data from 0945 - 1000. The data from 0900 to 0945 can't be found in the sysdiagnose.

Not sure if's the limitation or any setting I can change to increase the logging period?

Thanks.