Hi there!
Thanks for reaching out. I will try to help with your question.
Once you turn an event into a recurring event, the date is appended onto the end of the url, even on the original event.
There is not a setting to add this information to single events. It may be possible with some customization, but would require knowledge of working with rewrite rules. Unfortunately, this type of customization is a bit beyond what we can provide here in the support forums.
Let me know if that helps, or if you have any other questions.
Thanks,
Sky