Can I remove "timestamp"?

[Deanseo]

Taken the following screenshot of the published .html file as an example:

I'm hoping to get rid of the "00:00" part so it only shows "Date: 2019-09-28 Sat"

So far, I've tried the two attempts:

1. timestamp:nil

#+SETUPFILE: https://fniessen.github.io/org-html-themes/org/theme-readtheorg.setup                                                                                                                                                                                                                                                                                                       
#+TITLE: My title                                                                                                                                                                                                           
#+DATE:  [2019-05-25 Sat]    
                            
#+options: timestamp:nil 
~~~~~~~~~~~~~~~~~~~~~~~~                                                                                                                                                                                                                    

2. org-export-time-stamp-file
I've also set org-export-time-stamp-file to "%Y-%m-%d %a".

Unfortunately, both of the attempts take no effect and now I'm out of options.

In general, it's a nice feature to have, but in this case, I'm manually feeding the explicit date, whose timestamp is unimportant.

I'm not sure if this issue is with org-mode itself or with the theme - I'd love to have your advice.