RFC 5545, "Internet Calendaring and Scheduling Core Object Specification (iCalendar)", September 2009

Errata ID: 1913
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Anshul Agrawal
Date Reported: 2009-10-13
Verifier Name: Alexey Melnikov
Date Verified: 2010-07-07

Section 3.3.10 says:

represents the last Monday of the month.  The numeric value in a
BYDAY rule part with the FREQ rule part set to YEARLY corresponds
to an offset within the month when the BYMONTH rule part is
present, and corresponds to an offset within the year when the
BYWEEKNO or BYMONTH rule parts are present.  If an integer

It should say:

represents the last Monday of the month.  The numeric value in a
BYDAY rule part with the FREQ rule part set to YEARLY corresponds
to an offset within the month when the BYMONTH rule part is
present, and corresponds to an offset within the year when the
BYWEEKNO or BYMONTH rule parts are not present.  If an integer
                                   ^^^

Notes:

The original statement appears contradictory in itself.

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