When is the preload csv file updated on a mobile device?

What is the problem? Please be detailed.
I have a form that uses a csv list of choices, which resides in the -media folder. I will need to update this csv file frequently, but not the form. I have looked at the documentation (https://docs.opendatakit.org/form-update/) which suggests that csv can be updated without changing the version. That's good, and the explanation of versioning is clear.
However, it is not explicit about how to ensure that the device used for collection gets updated.

I know that the mobile device would need to be able to connect to Aggregate in order to update, so that's a 'given' but I'm not certain how to make sure that it happens and how the collector can check that easily.

I can see that the 'form management' options on Collect give the opportunity to do an update check and automatic download of forms - but does that include the csv and is it done 'silently'?

Does the date change on 'Fill Blank Form' screen to reflect that the media folder is updated? If not, that becomes a feature request... It would be good to show a date last checked too...

What ODK tool and version are you using? And on what device and operating system version?
1.18.1

Yes, it does an update check and the automatic download does include the all media. Perhaps you can try it and see what you think?

Hi Yaw,
Thanks for confirming that.

I just tried a push from Briefcase (v1.13.0) having updated only one of the CSV files in the media folder (of my Briefcase storage area). This is what happened:

Preparing for upload of form definition with 4 media attachments
Uploading form definition and 4 media attachments
UPLOAD FAILED: Form definition upload failed.  Detailed error: Conflict (409) while accessing: https://[my-odk].appspot.com/formUpload
Please verify that the URL, your user credentials and your permissions are all correct.
retrieving next chunk of instanceIds from server...
Partially successful upload...

I have checked that the user credentials are correct and the account has form manager and site admin permissions. I used the same details to pull the data to Briefcase to get the form definition and csv files.

I can't see how to replace those files directly by logging into Aggregate (which works with those same credentials) - I suspect it's not possible as it's not in the docs where I would expect to find it. I also checked to see if it had actually updated the csv in the 'partially successful upload', but no joy there.

I guess I'm doing something wrong?