How to change CKEditor styles dynamically via script? - ckeditor

Question

I a project I work on we need to restrict users with predefined styles that can be changed by the user.
In my jsFiddle the function setStyle() works. You can try out by uncommentting the setStyle([]). It seems to me that I can use the config.stylesSet = assignment only once.
The function to change the style does not work after a button click nor after setTimeout.
Is there any way to set styles via a script in CKE4 more than once?
CKEDITOR.stylesSet.add( 'my_styles', [
// Block-level styles
{ name: 'Blue Title', element: 'h2', styles: { 'color': 'Blue' } },
{ name: 'Red Title' , element: 'h3', styles: { 'color': 'Red' } },
// Inline styles
{ name: 'CSS Style', element: 'span', attributes: { 'class': 'my_style' } },
{ name: 'Marker: Yellow', element: 'span', styles: { 'background-color': 'Yellow' } }
] );
CKEDITOR.stylesSet.add( 'my_styles2', [
// Block-level styles
{ name: 'Default Title', element: 'h2', styles: { 'color': 'Red' } },
// Inline styles
{ name: 'CSS Style', element: 'span', attributes: { 'class': 'my_style' } },
] );
var ckeditor = CKEDITOR.inline('editor1', {
removePlugins: 'exportpdf,sourcearea',
fillEmptyBlocks : false,
});
// setStyle([])
setTimeout(() => {
console. log("resetting styles")
setStyle([])
}, 5000);
function setStyle(style){
// ckeditor.config.stylesSet = style
CKEDITOR.config.stylesSet = style
// console.log(ckeditor)
console.log(style)
}