When creating a new event in the Calendar, and you click on a day (say, in month view), the Start and End dates are pre-filled with the date you selected. That’s fine – as it should be.
However, when creating that new event, if you click on the Recurrence tab, and then click Daily, Weekly, etc., the “End by” date is pre-filled with today’s date, rather than the date selected on the calendar. Similarly (because today’s date is pre-filled), if you click on the calendar pop-up in the “End by” field, that pop-up starts with today’s month (and today is highlighted), rather than the month of the day (in the future) that you may have first selected on the calendar.
Thus, this is a minor bug. The pre-filled “End by” date in the Recurrence tab should function the same way that the “End” field does in the General tab when creating a new event, i.e., start with the date that was selected for the new event.