--- a/eric6/Plugins/VcsPlugins/vcsPySvn/SvnRevisionSelectionDialog.py	Mon Mar 01 17:48:43 2021 +0100
+++ b/eric6/Plugins/VcsPlugins/vcsPySvn/SvnRevisionSelectionDialog.py	Tue Mar 02 17:17:09 2021 +0100
@@ -68,7 +68,7 @@
         elif dateButton.isChecked():
             return "{{{0}}}".format(
                 QDateTime(dateEdit.date(), timeEdit.time())
-                .toString(Qt.ISODate))
+                .toString(Qt.DateFormat.ISODate))
         elif headButton.isChecked():
             return "HEAD"
         elif workingButton.isChecked():