The appellant shall file a reply brief, or a statement that a reply brief will not be filed, within the later of:
Fifteen days after the date of service of the respondent's brief, and 3 additional days under s. 801.15 (5) (a)
if service is accomplished by mail; or
Fifteen days after the date on which the court accepts the respondent's brief for filing.
The reply brief under par. (a)
shall comply with sub. (1) (e)
. If an unpublished opinion is cited under s. 809.23 (3) (a)
, a copy of the opinion shall be provided in an appendix to the reply brief.