Hello. I got an alert from webmaster tools about increased 404s on foursisterswinery.com. When I investigated, I found the issues were coming from the rss and ics feeds from the calendar.
We are using the default settings for the feeds. All plugins are up to date. I notice there was a recent update to mycalendar...presumably that is what caused the error.
The calendar may be seen at http://foursisterswinery.com/monthly-calendar/