diff --git a/adafruit_turtle.py b/adafruit_turtle.py
index b74881c..5944da4 100644
--- a/adafruit_turtle.py
+++ b/adafruit_turtle.py
@@ -641,12 +641,6 @@ def stamp(self, bitmap=None, palette=None):
         turtle position. Return a stamp_id for that stamp, which can be used to
         delete it by calling clearstamp(stamp_id).
         """
-        # The restriction on max_size in displayio.Group has been removed.
-        # For now, leave this with a limit of 6 so as not to break any
-        # deployed code.
-        if len(self._fg_addon_group) >= 6:
-            print("Addon group full")
-            return -1
         s_id = len(self._stamps)
         if self._turtle_pic is None:
             # easy.
@@ -660,11 +654,7 @@ def stamp(self, bitmap=None, palette=None):
             # odb bitmap
             new_stamp = displayio.TileGrid(
                 self._turtle_odb,
-                pixel_shader=getattr(
-                    self._turtle_odb, "pixel_shader", displayio.ColorConverter()
-                ),
-                # TODO: Once CP6 is no longer supported, replace the above line with below
-                # pixel_shader=self._turtle_odb.pixel_shader,
+                pixel_shader=self._turtle_odb.pixel_shader,
                 x=int(self._x - self._turtle_odb.width // 2),
                 y=int(self._y - self._turtle_odb.height // 2),
             )
@@ -701,8 +691,7 @@ def clearstamp(self, stampid):
                 if isinstance(self._stamps[stampid], tuple):
                     self._fg_addon_group.remove(self._stamps[stampid][0])
                     self._turtle_odb_use -= 1
-                    if self._turtle_odb_use == 0:
-                        self._stamps[stampid][1].close()
+
                 else:
                     self._fg_addon_group.remove(self._stamps[stampid])
                 self._stamps[stampid] = None
@@ -970,17 +959,14 @@ def bgpic(self, picname=None):
             if self._bg_pic is not None:
                 self._bg_addon_group.remove(self._odb_tilegrid)
                 self._odb_tilegrid = None
-                self._bg_pic.close()
                 self._bg_pic = None
                 self._bg_pic_filename = ""
         else:
-            with open(picname, "rb") as self._bg_pic:
-                odb = displayio.OnDiskBitmap(self._bg_pic)
+            odb = displayio.OnDiskBitmap(picname)
+
             self._odb_tilegrid = displayio.TileGrid(
                 odb,
-                pixel_shader=getattr(odb, "pixel_shader", displayio.ColorConverter()),
-                # TODO: Once CP6 is no longer supported, replace the above line with below
-                # pixel_shader=odb.pixel_shader,
+                pixel_shader=odb.pixel_shader,
             )
             self._bg_addon_group.append(self._odb_tilegrid)
             self._bg_pic_filename = picname
@@ -1069,8 +1055,6 @@ def changeturtle(self, source=None, dimensions=(12, 12)):
                 self._turtle_odb_use -= 1
                 self._turtle_odb = None
             if self._turtle_odb_file is not None:
-                if self._turtle_odb_use == 0:
-                    self._turtle_odb_file.close()
                 self._turtle_odb_file = None
             self._turtle_pic = None
             self._drawturtle()
@@ -1083,17 +1067,13 @@ def changeturtle(self, source=None, dimensions=(12, 12)):
                 self._turtle_alt_sprite = None
                 self._turtle_odb = None
                 if not isinstance(self._turtle_pic, tuple):
-                    self._turtle_odb_file.close()
                     self._turtle_odb_file = None
                     self._turtle_odb_use -= 1
                 self._turtle_pic = None
-            self._turtle_odb_file = open(  # pylint: disable=consider-using-with
-                source, "rb"
-            )
+
             try:
-                self._turtle_odb = displayio.OnDiskBitmap(self._turtle_odb_file)
+                self._turtle_odb = displayio.OnDiskBitmap(source)
             except:
-                self._turtle_odb_file.close()
                 self._turtle_odb_file = None
                 self._turtle_pic = None
                 if visible:
@@ -1103,11 +1083,7 @@ def changeturtle(self, source=None, dimensions=(12, 12)):
             self._turtle_pic = True
             self._turtle_alt_sprite = displayio.TileGrid(
                 self._turtle_odb,
-                pixel_shader=getattr(
-                    self._turtle_odb, "pixel_shader", displayio.ColorConverter()
-                ),
-                # TODO: Once CP6 is no longer supported, replace the above line with below
-                # pixel_shader=self._turtle_odb.pixel_shader,
+                pixel_shader=self._turtle_odb.pixel_shader,
             )
 
             if self._turtle_group:
@@ -1119,8 +1095,6 @@ def changeturtle(self, source=None, dimensions=(12, 12)):
             if self._turtle_pic is not None:
                 if self._turtle_odb_file is not None:
                     self._turtle_odb_use -= 1
-                    if self._turtle_odb_use == 0:
-                        self._turtle_odb_file.close()
             self._turtle_pic = dimensions
             self._turtle_alt_sprite = source
             if self._turtle_group: