title: iCalendar recurrence - Every sunday except last, even if the month has 4 or 5 Sundays
body: <p>I have an event that occur every sunday except last sunday.
  Therefore, when the month has 5 sundays it'll occur 4 times and when the month has 4 sundays it'll occur 3 times.</p>
  
  <p>Considering that Exrule is deprecated in RFC 5545, what is the best way to represent this in iCalendar?</p>