diff --git a/createhdds.py b/createhdds.py
index b941a23..4ee9965 100755
--- a/createhdds.py
+++ b/createhdds.py
@@ -272,7 +272,7 @@ class VirtInstallImage(object):
         variant = self.variant
         # From F31 onwards, Workstation tree is not installable and we
         # build Workstation images out of Everything
-        if variant == 'Workstation' and self.release.isdigit() and int(self.release) > 30:
+        if variant == 'Workstation' and str(self.release.isdigit()) and int(self.release) > 30:
             variant = 'Everything'
 
         try: