Template:Weekday before date
Usage
{{Weekday before date|Y|M|D|W|S}} uses the optional date format string S (defaults to "F d, Y") to return the date of the first W (=Sunday, Monday, ..., Saturday) before the specified date with year Y, month M, and day of month D.
The first Sunday before July 4, 2025 is given by "{{Weekday before date|2025|July|4|Sunday}}" as "June 29, 2025".