diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,9 @@
 
+40000.1.0
+=========
+
+ * Updated for mattermost-api version 40000.1.0.
+
 40000.0.1
 =========
 
diff --git a/mattermost-api-qc.cabal b/mattermost-api-qc.cabal
--- a/mattermost-api-qc.cabal
+++ b/mattermost-api-qc.cabal
@@ -1,5 +1,5 @@
 name:                mattermost-api-qc
-version:             40000.0.1
+version:             40000.1.0
 description:         A testing library for the mattermost-api library
 synopsis:            QuickCheck instances for the Mattermost client API library
 homepage:            https://github.com/matterhorn-chat/mattermost-api-qc
@@ -22,7 +22,7 @@
   exposed-modules:     Network.Mattermost.QuickCheck
   build-depends:       base >=4.4 && <5
                      , containers
-                     , mattermost-api == 40000.0.1
+                     , mattermost-api == 40000.1.0
                      , QuickCheck
                      , text
                      , time
diff --git a/src/Network/Mattermost/QuickCheck.hs b/src/Network/Mattermost/QuickCheck.hs
--- a/src/Network/Mattermost/QuickCheck.hs
+++ b/src/Network/Mattermost/QuickCheck.hs
@@ -114,7 +114,7 @@
           <$> genMaybe genPostId
           <*> genMaybe genPostId
           <*> genPostProps
-          <*> genText
+          <*> genMaybe genPostId
           <*> genSeq genFileId
           <*> genPostId
           <*> genPostType