[Theming App] Ho to automate

Hello all
Im currently playing around with the Theming app in Nextcloud 19.0.6

I was able to populate my Icons, Slogan, URL, etc. via script to my NC instance. It works very well. But i habe to trigger a update inside the app bevore it reflects the populated stuff.

Following command does not help:
sudo -u www-data php /var/www/nextcloud/occ maintenance:theme:update

Is there a way to trigger the Theming Apps Update via script?

Thanks in advance for your help

Ohh and Merry Chrismas to all of you :christmas_tree::star::santa: