Hi Mel,
Welcome back to the forums!
You can edit the template for the tooltip by following these instructions to copy it into your child theme. The file can be found at wp-content/plugins/the-events-calendar/src/views/month/tooltip.php.
For a quick CSS solution, you can add the following:
.tribe-events-tooltip .tribe-events-event-thumb {
float: right;
}
If you don’t see any changes initially, make sure to clear your browser/site cache, including unchecking the “Enable the Month View Cache” option under Events > Settings > Display. Let me know how it goes!
Thanks,
Jennifer