@NaughtyButNice69 According to this article one Ui 5.1 for the Tab S8 has started rolling out in some European countries, the wait should not be too long, updates come in batches though. https://www.sammobile.com/news/galaxy-tab-s8-one-ui-5-1-update-released-new-features/
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 5.0,Android 13 .