The Tenth Circuit has determined that if a non-citizen is granted voluntary departure, and wishes to file a motion to reopen, he must do so by the 60th day of his voluntary departure period, even if that day falls on a weekend.
The full text of Velazquez v. Garland can be found here:
https://www.ca10.uscourts.gov/sites/ca10/files/opinions/010110915861.pdf
An amended opinion can be found here: https://www.ca10.uscourts.gov/sites/ca10/files/opinions/010110969149.pdf