I have upgraded to 3.05, but the issue is still there. After a little delving, I think I might have found where the issue lies, or somewhere close to it. In
weekly-class-schedule/includes/wcs3_settings.php, there is an option for 'details_template' which is set to 'sanitize_text_field' (http://codex.wordpress.org/Function_Reference/sanitize_text_field). This is what is stripping the HTML out of the template and leaving me with
[class] [instructor] [start hour] to [end hour] [notes]
<p>[start hour] to [end hour]</p>
I hope that makes it a bit clearer for you to help me. I'm really pulling what little hair I have left out to find a solution.