diff --git a/source/python/mods/get_mars_data.py b/source/python/mods/get_mars_data.py
index e9c44e5eb06b0cd3fa2b9f6f675ed6cce719a867..d96075bb733000cdd9519ed1bf47a28448a4755c 100755
--- a/source/python/mods/get_mars_data.py
+++ b/source/python/mods/get_mars_data.py
@@ -258,7 +258,7 @@ def mk_dates(c, fluxes):
         if c.basetime == '00':
             start = start - timedelta(days=1)
 
-    if not purefc and fluxes:
+    if not c.purefc and fluxes:
         start = start - timedelta(days=1)
         end = end + timedelta(days=1)