Howdy Kate,
I would love to help you with this. We actually have a tutorial about altering the wording in the calendar. I would checkout that tutorial. We used the word recurring event in a number of phrases on the calendar, mostly in the backend. So I am not exactly sure which area you are hoping to modify. If you are trying to modify it on the front-end of your calendar, then likely the string you want to modify is ‘Recurring %s’. So you would to set this:
$custom_text = array(
'Recurring %s' => 'Other class dates available',
);
As per the tutorial.
Does that all make sense? Will that work for you? Please let me know.
Cheers!
– Brook