Source: Schema.org v30.1 vocabulary. Official byMonthDay property definition.
What does byMonthDay mean?
Defines the day(s) of the month on which a recurring [[Event]] takes place. Specified as an [[Integer]] between 1-31.
Used on types (domainIncludes)
Expected value types (rangeIncludes)
Schema.org domainIncludes and rangeIncludes are descriptive guidance, not strict validation prohibitions. Check the official reference for updates.
Related reference
Browse all Schema.org types and properties · Google feature support status