Thanks to Alex P for the heads up.
The executive producer of the show revealed that today is the last day of production on season 13 and they will be back for production on the next season in July, so CBS seems to have quietly renewed it.
Today is the last day of Production on Criminal Minds for S13. Today is day #171. Long hiatus coming, before returning to filming on 7/11/18. This season went fast as will our hiatus.
— Harry Bring (@LLPOS) March 28, 2018