The BYDAY rule part specifies a COMMA character (US-ASCII decimal 44)
separated list of days of the week;
And it can be used for monthly occurrences:
Each BYDAY value can also be preceded by a positive (+n) or negative
(-n) integer. If present, this indicates the nth occurrence of the
specific day within the MONTHLY or YEARLY RRULE.
Not sure how to get this information in yet, but it might be good to assume that it can, make sure the code works for it and then figure out the first part.
According to the rfc
BYDAY
is:And it can be used for monthly occurrences:
This should be supported.