public System.int SpecificDayOfMonth {get; set;}
Exago .NET API Documentation
SpecificDayOfMonth Property (ReportScheduleInfoMonthly)
When MonthlyPattern Property is SpecificDayOfMonth Field, this is the specific day of the month on which the schedule runs.
If a month does not have a day with that number (e.g. February does not have 31 days) then the system will "round" to the last day of the month.
public System.int SpecificDayOfMonth {get; set;}