diff --git a/cli/command_repository_set_parameters.go b/cli/command_repository_set_parameters.go
index 00e160129..4470f4575 100644
--- a/cli/command_repository_set_parameters.go
+++ b/cli/command_repository_set_parameters.go
@@ -121,9 +121,29 @@ func (c *commandRepositorySetParameters) setRetentionModeParameter(ctx context.C
 	log(ctx).Infof(" - setting %v to %s.\n", desc, v)
 }
 
-func (c *commandRepositorySetParameters) run(ctx context.Context, rep repo.DirectRepositoryWriter) error {
-	var anyChange bool
+func (c *commandRepositorySetParameters) updateEpochParameters(mp *format.MutableParameters, anyChange, upgradeToEpochManager *bool) {
+	*anyChange = true
 
+	if !mp.EpochParameters.Enabled {
+		mp.EpochParameters = epoch.DefaultParameters()
+		mp.IndexVersion = 2
+		*upgradeToEpochManager = true
+	}
+
+	if mp.Version < format.FormatVersion2 {
+		mp.Version = format.FormatVersion2
+	}
+}
+
+func (c *commandRepositorySetParameters) disableBlobRetention(ctx context.Context, blobcfg *format.BlobStorageConfiguration, anyChange *bool) {
+	log(ctx).Infof("disabling blob retention")
+
+	blobcfg.RetentionMode = ""
+	blobcfg.RetentionPeriod = 0
+	*anyChange = true
+}
+
+func (c *commandRepositorySetParameters) run(ctx context.Context, rep repo.DirectRepositoryWriter) error {
 	mp, err := rep.FormatManager().GetMutableParameters()
 	if err != nil {
 		return errors.Wrap(err, "mutable parameters")
@@ -139,38 +159,28 @@ func (c *commandRepositorySetParameters) run(ctx context.Context, rep repo.Direc
 		return errors.Wrap(err, "unable to get required features")
 	}
 
+	anyChange := false
 	upgradeToEpochManager := false
 
 	if c.upgradeRepositoryFormat {
-		anyChange = true
-
-		if !mp.EpochParameters.Enabled {
-			mp.EpochParameters = epoch.DefaultParameters()
-			mp.IndexVersion = 2
-			upgradeToEpochManager = true
-		}
-
-		if mp.Version < format.FormatVersion2 {
-			mp.Version = format.FormatVersion2
-		}
+		c.updateEpochParameters(&mp, &anyChange, &upgradeToEpochManager)
 	}
 
 	c.setSizeMBParameter(ctx, c.maxPackSizeMB, "maximum pack size", &mp.MaxPackSize, &anyChange)
 
 	// prevent downgrade of index format
-	if c.indexFormatVersion > mp.IndexVersion {
-		c.setIntParameter(ctx, c.indexFormatVersion, "index format version", &mp.IndexVersion, &anyChange)
-	} else if c.indexFormatVersion > 0 && c.indexFormatVersion != mp.IndexVersion {
-		return errors.Errorf("index format version can only be upgraded")
+	if c.indexFormatVersion != 0 {
+		if c.indexFormatVersion > mp.IndexVersion {
+			c.setIntParameter(ctx, c.indexFormatVersion, "index format version", &mp.IndexVersion, &anyChange)
+		} else {
+			return errors.Errorf("index format version can only be upgraded")
+		}
 	}
 
 	if c.retentionMode == "none" {
 		if blobcfg.IsRetentionEnabled() {
-			log(ctx).Infof("disabling blob retention")
-
-			blobcfg.RetentionMode = ""
-			blobcfg.RetentionPeriod = 0
-			anyChange = true
+			// disable blob retention if already enabled
+			c.disableBlobRetention(ctx, &blobcfg, &anyChange)
 		}
 	} else {
 		c.setRetentionModeParameter(ctx, blob.RetentionMode(c.retentionMode), "storage backend blob retention mode", &blobcfg.RetentionMode, &anyChange)
diff --git a/cli/command_repository_upgrade.go b/cli/command_repository_upgrade.go
index 9d3aeccec..f54c8a494 100644
--- a/cli/command_repository_upgrade.go
+++ b/cli/command_repository_upgrade.go
@@ -42,9 +42,8 @@ type commandRepositoryUpgrade struct {
 )
 
 const (
-	commitModeCommitOnValidationSuccess string = ""
-	commitModeAlwaysCommit                     = "always"
-	commitModeNeverCommit                      = "never"
+	commitModeAlwaysCommit = "always"
+	commitModeNeverCommit  = "never"
 )
 
 func (c *commandRepositoryUpgrade) setup(svc advancedAppServices, parent commandParent) {
@@ -91,22 +90,21 @@ func (c *commandRepositoryUpgrade) setup(svc advancedAppServices, parent command
 	c.svc = svc
 }
 
-// assign store the info struct in a map that can be used to compare indexes
+// assign store the info struct in a map that can be used to compare indexes.
 func assign(iif content.Info, i int, m map[content.ID][2]index.Info) {
 	v := m[iif.GetContentID()]
 	v[i] = iif
 	m[iif.GetContentID()] = v
 }
 
-// loadIndexBlobs load index blobs into indexEntries map
+// loadIndexBlobs load index blobs into indexEntries map.
 func loadIndexBlobs(ctx context.Context, indexEntries map[content.ID][2]index.Info, sm *content.SharedManager, which int, indexBlobInfos []content.IndexBlobInfo) error {
 	d := gather.WriteBuffer{}
-	
-	for _, indexBlobInfo := range indexBlobInfos {
 
+	for _, indexBlobInfo := range indexBlobInfos {
 		blobID := indexBlobInfo.BlobID
 
-		indexInfos, err := sm.LoadIndexBlob(ctx, blobID, d)
+		indexInfos, err := sm.LoadIndexBlob(ctx, blobID, &d)
 		if err != nil {
 			return errors.Wrapf(err, "failed to load index blob with BlobID %s", blobID)
 		}
@@ -114,15 +112,14 @@ func loadIndexBlobs(ctx context.Context, indexEntries map[content.ID][2]index.In
 		for _, indexInfo := range indexInfos {
 			assign(indexInfo, which, indexEntries)
 		}
-
 	}
+
 	return nil
 }
 
 // validateAction returns an error of the new V1 index blob content does not match the source V0 index blob content.
 // This is used to check that the upgraded index (V1 index) reflects the content of the old V0 index.
 func (c *commandRepositoryUpgrade) validateAction(ctx context.Context, rep repo.DirectRepositoryWriter) error {
-
 	indexEntries := map[content.ID][2]index.Info{}
 
 	sm := rep.ContentManager().SharedManager
@@ -158,10 +155,12 @@ func (c *commandRepositoryUpgrade) validateAction(ctx context.Context, rep repo.
 		} else {
 			err = checkIndexInfo(indexEntryPairs[0], indexEntryPairs[1])
 		}
+
 		if err != nil {
 			break
 		}
 	}
+
 	if err == nil {
 		log(ctx).Infof("index validation succeeded")
 		return nil
@@ -172,12 +171,14 @@ func (c *commandRepositoryUpgrade) validateAction(ctx context.Context, rep repo.
 		log(ctx).Errorf("%v", err)
 		return nil
 	}
+
 	return err
 }
 
 // checkIndexInfo compare two index infos.  If a mismatch exists, return an error with diagnostic information.
 func checkIndexInfo(i0, i1 index.Info) error {
 	var err error
+
 	switch {
 	case i0.GetFormatVersion() != i1.GetFormatVersion():
 		err = errors.Errorf("mismatched FormatVersions: %v %v", i0.GetFormatVersion(), i1.GetFormatVersion())
@@ -196,11 +197,13 @@ func checkIndexInfo(i0, i1 index.Info) error {
 	case i0.GetTimestampSeconds() != i1.GetTimestampSeconds():
 		err = errors.Errorf("mismatched TimestampSeconds: %v %v", i0.GetTimestampSeconds(), i1.GetTimestampSeconds())
 	}
+
 	if err != nil {
 		return errors.Wrapf(err, "index blobs do not match: %v, %v",
 			string(i0.GetPackBlobID()),
 			string(i1.GetPackBlobID()))
 	}
+
 	return nil
 }
 
@@ -429,6 +432,7 @@ func (c *commandRepositoryUpgrade) commitUpgrade(ctx context.Context, rep repo.D
 		log(ctx).Infof("Commit mode is set to 'never'.  Skipping commit.")
 		return nil
 	}
+
 	if err := rep.FormatManager().CommitUpgrade(ctx); err != nil {
 		return errors.Wrap(err, "error finalizing upgrade")
 	}
diff --git a/cli/command_repository_upgrade_test.go b/cli/command_repository_upgrade_test.go
index aaeaa4538..a1c18ab99 100644
--- a/cli/command_repository_upgrade_test.go
+++ b/cli/command_repository_upgrade_test.go
@@ -95,7 +95,6 @@ func (s *formatSpecificTestSuite) TestRepositoryCorruptedUpgrade(t *testing.T) {
 			"--status-poll-interval", "1s",
 			"--max-permitted-clock-drift", "1s")
 	}
-
 }
 
 func (s *formatSpecificTestSuite) TestRepositoryUpgradeCommitNever(t *testing.T) {
diff --git a/repo/content/committed_read_manager.go b/repo/content/committed_read_manager.go
index 2a03b94d1..ff05020cf 100644
--- a/repo/content/committed_read_manager.go
+++ b/repo/content/committed_read_manager.go
@@ -119,8 +119,8 @@ type SharedManager struct {
 }
 
 // LoadIndexBlob return index information loaded from the specified blob.
-func (sm *SharedManager) LoadIndexBlob(ctx context.Context, ibid blob.ID, d gather.WriteBuffer) ([]Info, error) {
-	err := sm.st.GetBlob(ctx, ibid, 0, -1, &d)
+func (sm *SharedManager) LoadIndexBlob(ctx context.Context, ibid blob.ID, d *gather.WriteBuffer) ([]Info, error) {
+	err := sm.st.GetBlob(ctx, ibid, 0, -1, d)
 	if err != nil {
 		return nil, errors.Wrapf(err, "could not find index blob %q", ibid)
 	}
diff --git a/repo/content/index_blob_manager_v0.go b/repo/content/index_blob_manager_v0.go
index c6e8ea487..46fe5e203 100644
--- a/repo/content/index_blob_manager_v0.go
+++ b/repo/content/index_blob_manager_v0.go
@@ -67,7 +67,6 @@ type indexBlobManagerV0 struct {
 
 // ListIndexBlobInfos list active blob info structs.  Also returns time of latest content deletion commit.
 func (m *indexBlobManagerV0) ListIndexBlobInfos(ctx context.Context) ([]IndexBlobInfo, time.Time, error) {
-
 	activeIndexBlobs, t0, err := m.listActiveIndexBlobs(ctx)
 	if err != nil {
 		return nil, time.Time{}, err
@@ -80,7 +79,7 @@ func (m *indexBlobManagerV0) ListIndexBlobInfos(ctx context.Context) ([]IndexBlo
 		if activeIndexBlob.BlobID == format.LegacyIndexPoisonBlobID {
 			continue
 		}
-		
+
 		q = append(q, activeIndexBlob)
 	}
 
diff --git a/tests/testenv/cli_test_env.go b/tests/testenv/cli_test_env.go
index 27091fa62..45f1dd31c 100644
--- a/tests/testenv/cli_test_env.go
+++ b/tests/testenv/cli_test_env.go
@@ -109,7 +109,7 @@ func (e *CLITest) RunAndExpectSuccess(t *testing.T, args ...string) []string {
 	return stdout
 }
 
-// TweakFile writes a 0x00 byte at a random point in a file.  Used to simulate file corruption
+// TweakFile writes a xor-ed byte at a random point in a file.  Used to simulate file corruption.
 func (e *CLITest) TweakFile(t *testing.T, dirn, fglob string) {
 	t.Helper()
 
@@ -118,13 +118,16 @@ func (e *CLITest) TweakFile(t *testing.T, dirn, fglob string) {
 	mch, err := fs.Glob(os.DirFS(dirn), fglob)
 	require.NoError(t, err)
 	require.Greater(t, len(mch), 0)
+
 	// grab a random file in the directory dirn
 	fn := mch[rand.Intn(len(mch))]
 	f, err := os.OpenFile(path.Join(dirn, fn), os.O_RDWR, os.FileMode(RwUserGroupOther))
 	require.NoError(t, err)
+
 	// find the length of the file, then seek to a random location
 	l, err := f.Seek(0, io.SeekEnd)
 	require.NoError(t, err)
+
 	i := rand.Int63n(l)
 	bs := [1]byte{}