Hi crharrison!
Good question. I imagine that the CSS tags for the event title must have been update between those two releases. You can certainly update the tag by creating a template override (more on this in our Themer’s Guide).
I think the easiest way, though, might be to update your custom styles to use the new CSS tag. That way, you only have to update the CSS file as opposed to creating a custom template override. 🙂
If you’re not sure which tags to use, here’s a handy tutorial on how to use DevTools to inspect element and identify the tags.
Will this help you get started? Please let me know. 🙂
Cheers!
Geoff