diff --git a/edosl0util/headers.py b/edosl0util/headers.py
index df27606c3c35cada2275e784cda3ecfb24f26d6f..f21c68c893c5c2c1e5efa4033d3026db78d8cb8c 100644
--- a/edosl0util/headers.py
+++ b/edosl0util/headers.py
@@ -35,7 +35,16 @@ class BaseStruct(c.BigEndianStructure):
         return '<%s (%s)>' % (self.__class__.__name__, fields)
 
 
-class AquaCucTimecode(BaseStruct):
+class Timecode(BaseStruct):
+
+    def astimestamp(self):
+        raise NotImplementedError()
+
+    def asdatetime(self):
+        raise NotImplementedError()
+
+
+class AquaCucTimecode(Timecode):
     """
     EOS AQUA implementation of a CCSDS Unsegmented Timecode. An CUT is an
     agency defined timecode which is in this case (I think) specific to Aqua.
@@ -71,7 +80,7 @@ class AquaCucTimecode(BaseStruct):
         return self.EPOCH + timedelta(seconds=seconds, microseconds=micros)
 
 
-class DaySegmentedTimecode(BaseStruct):
+class DaySegmentedTimecode(Timecode):
     _pack_ = 1
     _fields_ = [
         ('days', c.c_uint16),
@@ -216,16 +225,12 @@ def jpss_header_lookup(primary_header):
     grouping = primary_header.sequence_grouping
     if grouping == GROUP_FIRST:
         return JpssFirstSecondaryHeader
-        #elif grouping == GROUP_CONTINUING:
-        #    return JpssSecondaryHeader
-        #elif grouping == GROUP_LAST:
-        #    return JpssSecondaryHeader
     elif grouping == GROUP_STANDALONE:
         return JpssSecondaryHeader
 
 
-_aqua_headers = aqua_headers()
 def aqua_header_lookup(primary_header):  # noqa
     apid = primary_header.apid
     grouping = primary_header.sequence_grouping
     return _aqua_headers.get((apid, grouping))
+_aqua_headers = aqua_headers()
diff --git a/edosl0util/merge.py b/edosl0util/merge.py
index dd2a448738c74987038e6e8f8bd25f3aac6b023a..17b2a578d644afc3e70793f23e2515c9fd618118 100644
--- a/edosl0util/merge.py
+++ b/edosl0util/merge.py
@@ -9,10 +9,6 @@ from edosl0util.stream import (
     make_streams,
 )
 
-# date used as a flag value for comparissons
-_FLAG_DATE = datetime(1900, 1, 1)
-
-
 LOG = logging.getLogger(__name__)