diff --git a/rhizome.c b/rhizome.c
index 96a53711..f0c9a3f4 100644
--- a/rhizome.c
+++ b/rhizome.c
@@ -99,15 +99,17 @@ int rhizome_fetch_delay_ms()
  * operation will create it using the fields supplied.  Also, the caller can supply a clear-text
  * payload with the 'crypt=1' field to cause it to be stored encrypted.
  *
+ * - if 'appending' is true then the new bundle will be a journal bundle, otherwise it will be a
+ *   normal bundle.  Any existing manifest must be consistent; eg, an append will fail if a bundle
+ *   with the same Bundle Id already exists in the store and is not a journal.
+ *
  * - 'm' must point to a manifest structure into which any supplied partial manifest has already
  *   been parsed.  If the caller supplied no (partial) manifest at all, then the manifest 'm' will
  *   be blank.
  *
- * - 'bsk' must point to a supplied bundle secret parameter, or NULL if none was supplied.
+ * - 'mout' must point to a manifest pointer which is updated to hold the constructed manifest.
  *
- * - if 'appending' is true then the new bundle will be a journal bundle, otherwise it will be a
- *   normal bundle.  Any existing manifest must be consistent; eg, an append will fail if a bundle
- *   with the same Bundle Id already exists in the store and is not a journal.
+ * - 'bsk' must point to a supplied bundle secret parameter, or NULL if none was supplied.
  *
  * - 'author' must point to a supplied author parameter, or NULL if none was supplied.
  *
@@ -155,7 +157,13 @@ const char * rhizome_bundle_add_file(int appending,
       existing_manifest = NULL;
       break;
     case RHIZOME_BUNDLE_STATUS_SAME:
-      // Found a manifest with the same bundle ID.  Overwrite it with the supplied manifest.
+      // Found a manifest with the same bundle ID.  Unset its 'version', 'filesize' and 'filehash'
+      // fields unless appending, then overwrite it with the supplied manifest.
+      if (!appending) {
+	rhizome_manifest_del_version(existing_manifest);
+	rhizome_manifest_del_filesize(existing_manifest);
+	rhizome_manifest_del_filehash(existing_manifest);
+      }
       if (rhizome_manifest_overwrite(existing_manifest, m) == -1) {
 	WHY(reason = "Existing manifest could not be overwritten");
 	goto error;
@@ -182,18 +190,21 @@ const char * rhizome_bundle_add_file(int appending,
   // If no existing bundle has been identified, we are building a bundle from scratch.
   if (!new_manifest) {
     new_manifest = m;
-    // A new journal manifest needs these fields set so that the first append can succeed.
+    // A new journal manifest needs the 'filesize' and 'tail' fields set so that the first append can
+    // succeed.
     if (appending) {
-      rhizome_manifest_set_filesize(new_manifest, 0);
-      rhizome_manifest_set_tail(new_manifest, 0);
+      if (new_manifest->filesize == RHIZOME_SIZE_UNSET)
+	rhizome_manifest_set_filesize(new_manifest, 0);
+      if (new_manifest->tail == RHIZOME_SIZE_UNSET)
+	rhizome_manifest_set_tail(new_manifest, 0);
     }
   }
-  if (appending && !m->is_journal){
+  if (appending && !new_manifest->is_journal){
     // TODO: return a special status code for this case
     WHY(reason = "Cannot append to a non-journal");
     goto error;
   }
-  if (!appending && m->is_journal) {
+  if (!appending && new_manifest->is_journal) {
     // TODO: return a special status code for this case
     WHY(reason = "Cannot add a journal bundle (use append instead)");
     goto error;
diff --git a/rhizome.h b/rhizome.h
index babe587b..d4959692 100644
--- a/rhizome.h
+++ b/rhizome.h
@@ -251,8 +251,11 @@ typedef struct rhizome_manifest
  */
 #define rhizome_manifest_set_id(m,v)            _rhizome_manifest_set_id(__WHENCE__,(m),(v))
 #define rhizome_manifest_set_version(m,v)       _rhizome_manifest_set_version(__WHENCE__,(m),(v))
+#define rhizome_manifest_del_version(m)         _rhizome_manifest_del_version(__WHENCE__,(m))
 #define rhizome_manifest_set_filesize(m,v)      _rhizome_manifest_set_filesize(__WHENCE__,(m),(v))
+#define rhizome_manifest_del_filesize(m)        _rhizome_manifest_del_filesize(__WHENCE__,(m))
 #define rhizome_manifest_set_filehash(m,v)      _rhizome_manifest_set_filehash(__WHENCE__,(m),(v))
+#define rhizome_manifest_del_filehash(m)        _rhizome_manifest_del_filehash(__WHENCE__,(m))
 #define rhizome_manifest_set_tail(m,v)          _rhizome_manifest_set_tail(__WHENCE__,(m),(v))
 #define rhizome_manifest_set_bundle_key(m,v)    _rhizome_manifest_set_bundle_key(__WHENCE__,(m),(v))
 #define rhizome_manifest_del_bundle_key(m)      _rhizome_manifest_del_bundle_key(__WHENCE__,(m))
@@ -274,8 +277,11 @@ typedef struct rhizome_manifest
 
 void _rhizome_manifest_set_id(struct __sourceloc, rhizome_manifest *, const rhizome_bid_t *);
 void _rhizome_manifest_set_version(struct __sourceloc, rhizome_manifest *, uint64_t);
+void _rhizome_manifest_del_version(struct __sourceloc, rhizome_manifest *);
 void _rhizome_manifest_set_filesize(struct __sourceloc, rhizome_manifest *, uint64_t);
+void _rhizome_manifest_del_filesize(struct __sourceloc, rhizome_manifest *);
 void _rhizome_manifest_set_filehash(struct __sourceloc, rhizome_manifest *, const rhizome_filehash_t *);
+void _rhizome_manifest_del_filehash(struct __sourceloc, rhizome_manifest *);
 void _rhizome_manifest_set_tail(struct __sourceloc, rhizome_manifest *, uint64_t);
 void _rhizome_manifest_set_bundle_key(struct __sourceloc, rhizome_manifest *, const rhizome_bk_t *);
 void _rhizome_manifest_del_bundle_key(struct __sourceloc, rhizome_manifest *);
diff --git a/rhizome_bundle.c b/rhizome_bundle.c
index 9dd38311..359453fa 100644
--- a/rhizome_bundle.c
+++ b/rhizome_bundle.c
@@ -156,6 +156,11 @@ void _rhizome_manifest_set_version(struct __sourceloc __whence, rhizome_manifest
   m->finalised = 0;
 }
 
+void _rhizome_manifest_del_version(struct __sourceloc __whence, rhizome_manifest *m)
+{
+  _rhizome_manifest_set_version(__whence, m, 0);
+}
+
 void _rhizome_manifest_set_filesize(struct __sourceloc __whence, rhizome_manifest *m, uint64_t size)
 {
   if (size == RHIZOME_SIZE_UNSET) {
@@ -168,6 +173,11 @@ void _rhizome_manifest_set_filesize(struct __sourceloc __whence, rhizome_manifes
   m->finalised = 0;
 }
 
+void _rhizome_manifest_del_filesize(struct __sourceloc __whence, rhizome_manifest *m)
+{
+  _rhizome_manifest_set_filesize(__whence, m, RHIZOME_SIZE_UNSET);
+}
+
 /* Must always set file size before setting the file hash, to avoid assertion failures.
  */
 void _rhizome_manifest_set_filehash(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_filehash_t *hash)
@@ -185,6 +195,11 @@ void _rhizome_manifest_set_filehash(struct __sourceloc __whence, rhizome_manifes
   m->finalised = 0;
 }
 
+void _rhizome_manifest_del_filehash(struct __sourceloc __whence, rhizome_manifest *m)
+{
+  _rhizome_manifest_set_filehash(__whence, m, NULL);
+}
+
 void _rhizome_manifest_set_tail(struct __sourceloc __whence, rhizome_manifest *m, uint64_t tail)
 {
   if (tail == RHIZOME_SIZE_UNSET) {
@@ -193,9 +208,9 @@ void _rhizome_manifest_set_tail(struct __sourceloc __whence, rhizome_manifest *m
   } else {
     const char *v = rhizome_manifest_set_ui64(m, "tail", tail);
     assert(v); // TODO: remove known manifest fields from vars[]
-    m->tail = tail;
     m->is_journal = 1;
   }
+  m->tail = tail;
   m->finalised = 0;
 }
 
diff --git a/tests/rhizomeops b/tests/rhizomeops
index 2db21db4..023a24a7 100755
--- a/tests/rhizomeops
+++ b/tests/rhizomeops
@@ -765,17 +765,29 @@ test_AddUpdateDiscoverAuthor() {
 
 doc_AddUpdateNoAuthor="Cannot add new payload to authorless manifest"
 setup_AddUpdateNoAuthor() {
-   setup_AddUpdateNewVersion
-   $SED -i -e '/^BK=/d' file1_2.manifest
+   setup_servald
+   setup_rhizome
+   executeOk_servald rhizome list
+   assert_rhizome_list
+   echo "A test file" >file1
+   echo "A test file, second version" >file1_2
+   # Add first file
+   executeOk_servald rhizome add file '' file1 file1.manifest
+   extract_stdout_secret file1_secret
+   assert_manifest_fields file1.manifest !BK
+   # Create second manifest
+   cp file1.manifest file1_2.manifest
+   strip_signatures file1_2.manifest
+   $SED -i -e '/^date=/d;/^filehash=/d;/^filesize=/d;/^version=/d' file1_2.manifest
+   tfw_cat -v file1_2.manifest
 }
 test_AddUpdateNoAuthor() {
-   tfw_cat -v file1_2.manifest
    execute $servald rhizome add file $SIDB1 file1_2 file1_2.manifest
    tfw_cat --stderr
    assertExitStatus '!=' 0
-   # Rhizome store contents have old payload, with the original author.
+   # Rhizome store contents still have old payload
    executeOk_servald rhizome list
-   assert_rhizome_list --fromhere=1 --author=$SIDB1 file1 file2
+   assert_rhizome_list --fromhere=0 file1
 }
 
 doc_AddUpdateNoAuthorWithSecret="Add new payload to authorless manifest with bundle secret"
@@ -783,13 +795,12 @@ setup_AddUpdateNoAuthorWithSecret() {
    setup_AddUpdateNoAuthor
 }
 test_AddUpdateNoAuthorWithSecret() {
-   tfw_cat -v file1_2.manifest
    executeOk_servald rhizome add file $SIDB1 file1_2 file1_2.manifest "$file1_secret"
    tfw_cat --stderr
    # Rhizome store contents have new payload, but it has lost its author (no BK
    # field any more).
    executeOk_servald rhizome list
-   assert_rhizome_list --fromhere=0 file1_2 --fromhere=1 --author=$SIDB1 file2
+   assert_rhizome_list --fromhere=0 file1_2
 }
 
 doc_AddUpdateAutoVersion="Add new payload to existing manifest with automatic version"