@arianwen27 noticed the beta is actually marked as a release version not a beta version. I wonder if this is the problem as Smart switch probably needs to see the beta flag to offer the downgrade option.
Possibly that is the reason and to be sorted out at Samsung 's end. However know in the past some customers had issues really back in the early stages with no downgrade option available. It was resolved in the end.
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
To be honest I'm pretty happy with it. Did have a strange thing yesterday where it appeared to have activated airplane mode on its own. Then noticed that battery saver was also on? I reported both in the beta forum. Not happened again though.