diff --git a/commands/create.go b/commands/create.go
index 63ae4de0..657d6618 100644
--- a/commands/create.go
+++ b/commands/create.go
@@ -29,7 +29,7 @@ func runCreate(dockerCli command.Cli, in createOptions, args []string) error {
 	ctx := appcontext.Context()
 
 	if in.name == "default" {
-		return errors.Errorf("default is a reserved name and can't be used to identify builder instance")
+		return errors.Errorf("default is a reserved name and cannot be used to identify builder instance")
 	}
 
 	if in.actionLeave {
@@ -91,6 +91,12 @@ func runCreate(dockerCli command.Cli, in createOptions, args []string) error {
 		}
 	}
 
+	if ng != nil {
+		if in.nodeName == "" && !in.actionAppend {
+			return errors.Errorf("existing instance for %s but no append mode, specify --node to make changes for existing instances", name)
+		}
+	}
+
 	if ng == nil {
 		ng = &store.NodeGroup{
 			Name: name,
diff --git a/commands/inspect.go b/commands/inspect.go
index 3707b943..e21fa01e 100644
--- a/commands/inspect.go
+++ b/commands/inspect.go
@@ -77,11 +77,15 @@ func runInspect(dockerCli command.Cli, in inspectOptions, args []string) error {
 	err = loadNodeGroupData(timeoutCtx, dockerCli, ngi)
 
 	if in.bootstrap {
-		if err := boot(ctx, ngi); err != nil {
+		var ok bool
+		ok, err = boot(ctx, ngi)
+		if err != nil {
 			return err
 		}
-		ngi = &nginfo{ng: ng}
-		err = loadNodeGroupData(ctx, dockerCli, ngi)
+		if ok {
+			ngi = &nginfo{ng: ng}
+			err = loadNodeGroupData(ctx, dockerCli, ngi)
+		}
 	}
 
 	w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0)
@@ -92,22 +96,24 @@ func runInspect(dockerCli command.Cli, in inspectOptions, args []string) error {
 	} else if ngi.err != nil {
 		fmt.Fprintf(w, "Error:\t%s\n", ngi.err.Error())
 	}
-	fmt.Fprintln(w, "")
-	fmt.Fprintln(w, "Nodes:")
-
-	for i, n := range ngi.ng.Nodes {
-		if i != 0 {
-			fmt.Fprintln(w, "")
-		}
-		fmt.Fprintf(w, "Name:\t%s\n", n.Name)
-		fmt.Fprintf(w, "Endpoint:\t%s\n", n.Endpoint)
-		if err := ngi.drivers[i].di.Err; err != nil {
-			fmt.Fprintf(w, "Error:\t%s\n", err.Error())
-		} else if err := ngi.drivers[i].err; err != nil {
-			fmt.Fprintf(w, "Error:\t%s\n", err.Error())
-		} else {
-			fmt.Fprintf(w, "Status:\t%s\n", ngi.drivers[i].info.Status)
-			fmt.Fprintf(w, "Platforms:\t%s\n", strings.Join(append(n.Platforms, ngi.drivers[i].platforms...), ", "))
+	if err == nil {
+		fmt.Fprintln(w, "")
+		fmt.Fprintln(w, "Nodes:")
+
+		for i, n := range ngi.ng.Nodes {
+			if i != 0 {
+				fmt.Fprintln(w, "")
+			}
+			fmt.Fprintf(w, "Name:\t%s\n", n.Name)
+			fmt.Fprintf(w, "Endpoint:\t%s\n", n.Endpoint)
+			if err := ngi.drivers[i].di.Err; err != nil {
+				fmt.Fprintf(w, "Error:\t%s\n", err.Error())
+			} else if err := ngi.drivers[i].err; err != nil {
+				fmt.Fprintf(w, "Error:\t%s\n", err.Error())
+			} else {
+				fmt.Fprintf(w, "Status:\t%s\n", ngi.drivers[i].info.Status)
+				fmt.Fprintf(w, "Platforms:\t%s\n", strings.Join(append(n.Platforms, ngi.drivers[i].platforms...), ", "))
+			}
 		}
 	}
 
@@ -137,7 +143,7 @@ func inspectCmd(dockerCli command.Cli) *cobra.Command {
 	return cmd
 }
 
-func boot(ctx context.Context, ngi *nginfo) error {
+func boot(ctx context.Context, ngi *nginfo) (bool, error) {
 	toBoot := make([]int, 0, len(ngi.drivers))
 	for i, d := range ngi.drivers {
 		if d.err != nil || d.di.Err != nil || d.di.Driver == nil || d.info == nil {
@@ -148,7 +154,7 @@ func boot(ctx context.Context, ngi *nginfo) error {
 		}
 	}
 	if len(toBoot) == 0 {
-		return nil
+		return false, nil
 	}
 
 	pw := progress.NewPrinter(context.TODO(), os.Stderr, "auto")
@@ -171,5 +177,5 @@ func boot(ctx context.Context, ngi *nginfo) error {
 		}(idx)
 	}
 
-	return eg.Wait()
+	return true, eg.Wait()
 }
diff --git a/commands/ls.go b/commands/ls.go
index c15c9d39..2f867586 100644
--- a/commands/ls.go
+++ b/commands/ls.go
@@ -90,7 +90,7 @@ func runLs(dockerCli command.Cli, in lsOptions) error {
 	}
 
 	w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0)
-	fmt.Fprintf(w, "NAME\tDRIVER/ENDPOINT\tSTATUS\tPLATFORMS\n")
+	fmt.Fprintf(w, "NAME/NODE\tDRIVER/ENDPOINT\tSTATUS\tPLATFORMS\n")
 
 	currentSet := false
 	for _, b := range builders {
diff --git a/commands/use.go b/commands/use.go
index c92d2a06..9b55a2ac 100644
--- a/commands/use.go
+++ b/commands/use.go
@@ -39,7 +39,7 @@ func runUse(dockerCli command.Cli, in useOptions, name string) error {
 			}
 			for _, l := range list {
 				if l.Name == name {
-					return errors.Errorf("to switch to context %s use `docker context use %s`", name, name)
+					return errors.Errorf("run `docker context use %s` to switch to context %s", name, name)
 				}
 			}
 
diff --git a/commands/util.go b/commands/util.go
index 41bd3d87..969471e3 100644
--- a/commands/util.go
+++ b/commands/util.go
@@ -285,7 +285,8 @@ func loadNodeGroupData(ctx context.Context, dockerCli command.Cli, ngi *nginfo)
 	}
 	ngi.drivers = make([]dinfo, len(dis))
 	for i, di := range dis {
-		ngi.drivers[i].di = &di
+		d := di
+		ngi.drivers[i].di = &d
 		func(d *dinfo) {
 			eg.Go(func() error {
 				if err := loadInfoData(ctx, d); err != nil {
diff --git a/store/nodegroup.go b/store/nodegroup.go
index 56a489b2..21a4816b 100644
--- a/store/nodegroup.go
+++ b/store/nodegroup.go
@@ -33,6 +33,9 @@ func (ng *NodeGroup) Leave(name string) error {
 func (ng *NodeGroup) Update(name, endpoint string, platforms []string, endpointsSet bool, actionAppend bool) error {
 	i := ng.findNode(name)
 	if i == -1 && !actionAppend {
+		if len(ng.Nodes) > 0 {
+			return errors.Errorf("node %s not found, did you mean to append?", name)
+		}
 		ng.Nodes = nil
 	}
 	if i != -1 {
@@ -87,13 +90,12 @@ func (ng *NodeGroup) validateDuplicates(ep string) error {
 }
 
 func (ng *NodeGroup) findNode(name string) int {
-	i := -1
-	for ii, n := range ng.Nodes {
+	for i, n := range ng.Nodes {
 		if n.Name == name {
-			i = ii
+			return i
 		}
 	}
-	return i
+	return -1
 }
 
 func (ng *NodeGroup) nextNodeName() string {