diff --git a/ANNOUNCE b/ANNOUNCE
index af1ddf5..960b0eb 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,4 +1,4 @@
-Libpng 1.6.33rc02 - September 20, 2017
+Libpng 1.6.33rc02 - September 22, 2017
 
 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.
@@ -49,13 +49,14 @@
 Version 1.6.33rc01 [September 20, 2017]
   Initialize memory allocated by png_inflate to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in png_set_text_2()
-    due to truncated iTXT or zTXT chunk.
+    due to truncated iTXt or zTXt chunk.
   Initialize memory allocated by png_read_buffer to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in
     png_icc_check_tag_table() due to truncated iCCP chunk.
   Removed a redundant test (suggested by "irwir" in Github issue #180).
 
-Version 1.6.33rc02 [September 20, 2017]
+Version 1.6.33rc02 [September 22, 2017]
+  Added interlaced versions of each file in contrib/pngsuite.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index ded4915..c775213 100644
--- a/CHANGES
+++ b/CHANGES
@@ -833,7 +833,7 @@
   Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes
     which are no longer used.
   Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is
-    defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED
+    defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXt_SUPPORTED
     is defined.
   Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory
     overrun when old applications fill the info_ptr->text structure directly.
@@ -6019,13 +6019,14 @@
 Version 1.6.33rc01 [September 20, 2017]
   Initialize memory allocated by png_inflate to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in png_set_text_2()
-    due to truncated iTXT or zTXT chunk.
+    due to truncated iTXt or zTXt chunk.
   Initialize memory allocated by png_read_buffer to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in
     png_icc_check_tag_table() due to truncated iCCP chunk.
   Removed a redundant test (suggested by "irwir" in Github issue #180).
 
-Version 1.6.33rc02 [September 20, 2017]
+Version 1.6.33rc02 [September 22, 2017]
+  Added interlaced versions of each file in contrib/pngsuite.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/contrib/pngsuite/README b/contrib/pngsuite/README
index 53ba5c8..930aeae 100644
--- a/contrib/pngsuite/README
+++ b/contrib/pngsuite/README
@@ -16,6 +16,8 @@
 The "ft*.png" images are "free/libre" replacements for the transparent
 corresponding t*.png images in the PngSuite.
 
+The "i*.png" images are the same complete set, but interlaced.
+
 The images in this directory represent the basic PNG color-types:
 grayscale (1-16 bit deep), full color (8 or 16 bit), paletted
 (1-8 bit) and grayscale or color images with alpha channel. You
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