diff --git a/ANNOUNCE b/ANNOUNCE
index 1ed791e..ebe373b 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,4 +1,4 @@
-Libpng 1.6.21beta01 - December 9, 2015
+Libpng 1.6.21beta01 - December 11, 2015
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -25,9 +25,9 @@
 
 Changes since the last public release (1.6.20):
 
-Version 1.6.21beta01 [December 9, 2015]
-  Fixed a syntax error in tests/pngstest that some shells other than
-    bash could not parse (Bug report by Nelson Beebe).
+Version 1.6.21beta01 [December 11, 2015]
+  Fixed syntax "$(command)" in tests/pngstest that some shells other than
+    bash could not parse (Bug report by Nelson Beebe). Use `command` instead.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index 64b98bd..b7dafe3 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5446,9 +5446,9 @@
 Version 1.6.20 [December 3, 2015]
   No changes.
 
-Version 1.6.21beta01 [December 9, 2015]
-  Fixed a syntax error in tests/pngstest that some shells other than
-    bash could not parse (Bug report by Nelson Beebe).
+Version 1.6.21beta01 [December 11, 2015]
+  Fixed syntax "$(command)" in tests/pngstest that some shells other than
+    bash could not parse (Bug report by Nelson Beebe). Use `command` instead.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/LICENSE b/LICENSE
index 016b6d3..df83570 100644
--- a/LICENSE
+++ b/LICENSE
@@ -10,7 +10,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 9, 2015, are
+libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 11, 2015, are
 Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -109,4 +109,4 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-December 9, 2015
+December 11, 2015
diff --git a/README b/README
index fb64fc1..4725c03 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-README for libpng version 1.6.21beta01 - December 9, 2015 (shared library 16.0)
+README for libpng version 1.6.21beta01 - December 11, 2015 (shared library 16.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
diff --git a/libpng-manual.txt b/libpng-manual.txt
index 290a25a..c416788 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.21beta01 - December 9, 2015
+ libpng version 1.6.21beta01 - December 11, 2015
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.21beta01 - December 9, 2015
+ libpng versions 0.97, January 1998, through 1.6.21beta01 - December 11, 2015
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
 
diff --git a/libpng.3 b/libpng.3
index 3986f10..2c0bc3a 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "December 9, 2015"
+.TH LIBPNG 3 "December 11, 2015"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.6.21beta01
 .SH SYNOPSIS
@@ -508,7 +508,7 @@
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.21beta01 - December 9, 2015
+ libpng version 1.6.21beta01 - December 11, 2015
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
@@ -519,7 +519,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.21beta01 - December 9, 2015
+ libpng versions 0.97, January 1998, through 1.6.21beta01 - December 11, 2015
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
 
@@ -5990,7 +5990,7 @@
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.6.21beta01 - December 9, 2015:
+Libpng version 1.6.21beta01 - December 11, 2015:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -6015,7 +6015,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 9, 2015, are
+libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 11, 2015, are
 Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -6114,7 +6114,7 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-December 9, 2015
+December 11, 2015
 
 .\" end of man page
 
diff --git a/libpngpf.3 b/libpngpf.3
index b86288f..37ef5c6 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,4 +1,4 @@
-.TH LIBPNGPF 3 "December 9, 2015"
+.TH LIBPNGPF 3 "December 11, 2015"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.6.21beta01
 (private functions)
diff --git a/png.5 b/png.5
index 4ce3bbd..228ad17 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "December 9, 2015"
+.TH PNG 5 "December 11, 2015"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
diff --git a/png.c b/png.c
index 07b8f89..e1ab648 100644
--- a/png.c
+++ b/png.c
@@ -775,13 +775,13 @@
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.21beta01 - December 9, 2015" PNG_STRING_NEWLINE \
+      "libpng version 1.6.21beta01 - December 11, 2015" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2015 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
       "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
       PNG_STRING_NEWLINE;
 #  else
-   return "libpng version 1.6.21beta01 - December 9, 2015\
+   return "libpng version 1.6.21beta01 - December 11, 2015\
       Copyright (c) 1998-2015 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
diff --git a/png.h b/png.h
index 5a0d152..16f9b3d 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.21beta01, December 9, 2015
+ * libpng version 1.6.21beta01, December 11, 2015
  *
  * Copyright (c) 1998-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.21beta01, December 9, 2015:
+ *   libpng versions 0.97, January 1998, through 1.6.21beta01, December 11, 2015:
  *     Glenn Randers-Pehrson.
  *   See also "Contributing Authors", below.
  */
@@ -25,7 +25,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 9, 2015, are
+ * libpng versions 1.0.7, July 1, 2000, through 1.6.21beta01, December 11, 2015, are
  * Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, and are distributed according to the same
  * disclaimer and license as libpng-1.0.6 with the following individuals
@@ -214,7 +214,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    December 9, 2015
+ *    December 11, 2015
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -284,7 +284,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.6.21beta01"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.6.21beta01 - December 9, 2015\n"
+     " libpng version 1.6.21beta01 - December 11, 2015\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
diff --git a/pngconf.h b/pngconf.h
index d6a85a9..2ce1bb2 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.6.21beta01, December 9, 2015
+ * libpng version 1.6.21beta01, December 11, 2015
  *
  * Copyright (c) 1998-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/projects/vstudio/readme.txt b/projects/vstudio/readme.txt
index faff32d..103e681 100644
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.6.21beta01 - December 9, 2015
+libpng version 1.6.21beta01 - December 11, 2015
 
 Copyright (c) 1998-2010 Glenn Randers-Pehrson
 
diff --git a/projects/vstudio/zlib.props b/projects/vstudio/zlib.props
index 5e71b54..c4d88e6 100644
--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.6.21beta01 - December 9, 2015
+ * libpng version 1.6.21beta01 - December 11, 2015
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *
diff --git a/scripts/README.txt b/scripts/README.txt
index e7b80dc..17549a0 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,5 +1,5 @@
 
-Makefiles for  libpng version 1.6.21beta01 - December 9, 2015
+Makefiles for  libpng version 1.6.21beta01 - December 11, 2015
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index 9ffd52d..3ba5a0b 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -2,7 +2,7 @@
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng version 1.6.21beta01 - December 9, 2015 */
+/* Libpng version 1.6.21beta01 - December 11, 2015 */
 
 /* Copyright (c) 1998-2015 Glenn Randers-Pehrson */