How to customize the format of timestamps?

In this page of the user documentation of JabRef, it says the format of timestamps can be customized and gives designators for customization. I would like to avoid adding time in generated timestamps, but I find no place to edit the format for timestamps. Where should I put these format designators?

I am running JabRef 5.5 on macOS 11.5.1. The test is done with checking “Add timestamps to …” after resetting options and restarting JabRef.

hmmm could be that this is outdated documentation, which should be removed from the webpage.

As far as I am aware the timestamps field has been replaced by creationdate and modificationdate fields. The timestamp field is not an official BibTeX or BibLaTeX field. Neither apparently is creationdate (Jabref is trying to follow bibtex and biblatex standards as close as possible wherever it makes sense). I am not aware for the cause of this switch, but I could imagine it has something to do with interoperability and the ability to import bibliographic data from - and export to - other literature management programs.

Creationdate and Modificationdate follow ISO 8601. If you want to have a laugh, please check this meme about ISO 8601.

You can enable / disable automatic creation of these fields here:

Maybe timestamp should be classified as “deprecated” field.