set
If period is MONTHLY, set byDay setting so that the recurrence happens on a day of a week in the month. If both parameters are 0, the week number and day of the week will be the same as start date's.
Parameters
day
Day of the week, use DaysOfWeek constants.
week
On which week of the month the events will happen, starting from 1. From -4 to 4, negative values count the week number from the end of the month.