diff --git a/cmd/common.go b/cmd/common.go
index d24833619..1eeb78567 100644
--- a/cmd/common.go
+++ b/cmd/common.go
@@ -152,20 +152,7 @@ func syncMain(ctx context.Context, filenames []string, dry bool, parallelism,
 		}
 		return fmt.Errorf(
 			"cannot apply '%s' config format version to Kong version 3.0 or above.\n"+
-				"Please upgrade your configuration to account for 3.0\n"+
-				"breaking changes using the following command:\n\n"+
-				"deck convert --from kong-gateway-2.x --to kong-gateway-3.x\n\n"+
-				"This command performs the following changes:\n"+
-				"  - upgrade the `_format_version` value to `3.0`\n"+
-				"  - add the `~` prefix to all routes' paths containing a regex-pattern\n\n"+
-				"These changes may not be correct or exhaustive enough.\n"+
-				"It is strongly recommended to perform a manual audit\n"+
-				"of the updated configuration file before applying\n"+
-				"the configuration in production. Incorrect changes will result in\n"+
-				"unintended traffic routing by Kong Gateway.\n\n"+
-
-				"For more information about this and related changes,\n"+
-				"please visit: https://docs.konghq.com/deck/latest/3.0-upgrade", formatVersion)
+				utils.UpgradeMessage, formatVersion)
 	}
 
 	// TODO: instead of guessing the cobra command here, move the sendAnalytics
diff --git a/convert/convert.go b/convert/convert.go
index c328773f8..49843efd9 100644
--- a/convert/convert.go
+++ b/convert/convert.go
@@ -82,13 +82,39 @@ func convertKongGateway2xTo3x(input *file.Content, filename string) (*file.Conte
 	outputContent := input.DeepCopy()
 
 	convertedRoutes := []*file.FRoute{}
+	changedRoutes := []string{}
 	for _, service := range outputContent.Services {
 		for _, route := range service.Routes {
-			convertedRoutes = append(convertedRoutes, migrateRoutesPathFieldPre300(route, filename))
+			route, hasChanged := migrateRoutesPathFieldPre300(route)
+			convertedRoutes = append(convertedRoutes, route)
+			if hasChanged {
+				if route.ID != nil {
+					changedRoutes = append(changedRoutes, *route.ID)
+				} else {
+					changedRoutes = append(changedRoutes, *route.Name)
+				}
+			}
 		}
 		service.Routes = convertedRoutes
 	}
 
+	if len(changedRoutes) > 0 {
+		changedRoutesLen := len(changedRoutes)
+		// do not consider more than 10 sample routes to print out.
+		if changedRoutesLen > 10 {
+			changedRoutes = changedRoutes[:10]
+		}
+		cprint.UpdatePrintf(
+			"From the '%s' config file,\n"+
+				"%d unsupported routes' paths format with Kong version 3.0\n"+
+				"or above were detected. Some of these routes are (not an exhaustive list):\n\n"+
+				"%s\n\n"+
+				"Kong gateway versions 3.0 and above require that regular expressions\n"+
+				"start with a '~' character to distinguish from simple prefix match.\n"+
+				"In order to make these paths compatible with 3.x, a '~' prefix has been added.\n\n",
+			filename, changedRoutesLen, strings.Join(changedRoutes, "\n"))
+	}
+
 	cprint.UpdatePrintf(
 		"From the '%s' config file,\n"+
 			"the _format_version field has been migrated from '%s' to '%s'.\n"+
@@ -102,31 +128,15 @@ func convertKongGateway2xTo3x(input *file.Content, filename string) (*file.Conte
 	return outputContent, nil
 }
 
-func migrateRoutesPathFieldPre300(route *file.FRoute, filename string) *file.FRoute {
-	changedPaths := []string{}
+func migrateRoutesPathFieldPre300(route *file.FRoute) (*file.FRoute, bool) {
+	var hasChanged bool
 	for _, path := range route.Paths {
 		if !strings.HasPrefix(*path, "~/") && utils.IsPathRegexLike(*path) {
-			changedPaths = append(changedPaths, *path)
 			*path = "~" + *path
+			hasChanged = true
 		}
 	}
-	if len(changedPaths) > 0 {
-		changedPathsLen := len(changedPaths)
-		// do not consider more than 3 sample routes to print out.
-		if changedPathsLen > 3 {
-			changedPaths = changedPaths[:3]
-		}
-		cprint.UpdatePrintf(
-			"From the '%s' config file,\n"+
-				"%d routes paths matching an unsupported regex pattern usage\n"+
-				"with Kong version 3.0 or above were detected\n"+
-				"(e.g. %s).\n\n"+
-				"Kong gateway versions 3.0 and above require that regular expressions\n"+
-				"start with a '~' character to distinguish from simple prefix match.\n"+
-				"In order to make these paths compatible with 3.x, a '~' prefix has been added.\n\n",
-			filename, changedPathsLen, strings.Join(changedPaths, ", "))
-	}
-	return route
+	return route, hasChanged
 }
 
 func convertKongGatewayToKonnect(input *file.Content) (*file.Content, error) {
diff --git a/file/builder.go b/file/builder.go
index edb093ad2..3abce7ff6 100644
--- a/file/builder.go
+++ b/file/builder.go
@@ -609,6 +609,24 @@ func (b *stateBuilder) routes() {
 			return
 		}
 	}
+
+	// check routes' paths format
+	if b.checkRoutePaths {
+		unsupportedRoutes := []string{}
+		allRoutes, err := b.intermediate.Routes.GetAll()
+		if err != nil {
+			b.err = err
+			return
+		}
+		for _, r := range allRoutes {
+			if utils.HasPathsWithRegex300AndAbove(r.Route) {
+				unsupportedRoutes = append(unsupportedRoutes, *r.Route.ID)
+			}
+		}
+		if len(unsupportedRoutes) > 0 {
+			utils.PrintRouteRegexWarning(unsupportedRoutes)
+		}
+	}
 }
 
 func (b *stateBuilder) enterprise() {
@@ -799,10 +817,6 @@ func (b *stateBuilder) ingestRoute(r FRoute) error {
 		return err
 	}
 
-	if b.checkRoutePaths {
-		utils.CheckRoutePaths300AndAbove(r.Route)
-	}
-
 	// plugins for the route
 	var plugins []FPlugin
 	for _, p := range r.Plugins {
diff --git a/tests/integration/sync_test.go b/tests/integration/sync_test.go
index 29d325d80..7f68afe4c 100644
--- a/tests/integration/sync_test.go
+++ b/tests/integration/sync_test.go
@@ -1803,20 +1803,7 @@ func Test_Sync_Unsupported_Formats(t *testing.T) {
 			kongFile: "testdata/sync/001-create-a-service/kong.yaml",
 			expectedError: errors.New(
 				"cannot apply '1.1' config format version to Kong version 3.0 or above.\n" +
-					"Please upgrade your configuration to account for 3.0\n" +
-					"breaking changes using the following command:\n\n" +
-					"deck convert --from kong-gateway-2.x --to kong-gateway-3.x\n\n" +
-					"This command performs the following changes:\n" +
-					"  - upgrade the `_format_version` value to `3.0`\n" +
-					"  - add the `~` prefix to all routes' paths containing a regex-pattern\n\n" +
-					"These changes may not be correct or exhaustive enough.\n" +
-					"It is strongly recommended to perform a manual audit\n" +
-					"of the updated configuration file before applying\n" +
-					"the configuration in production. Incorrect changes will result in\n" +
-					"unintended traffic routing by Kong Gateway.\n\n" +
-
-					"For more information about this and related changes,\n" +
-					"please visit: https://docs.konghq.com/deck/latest/3.0-upgrade"),
+					utils.UpgradeMessage),
 		},
 	}
 	for _, tc := range tests {
diff --git a/utils/utils.go b/utils/utils.go
index 05ffe9fb6..e00f37c6b 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -23,6 +23,21 @@ var (
 	Kong300Version = semver.MustParse("3.0.0")
 )
 
+var UpgradeMessage = "Please upgrade your configuration to account for 3.0\n" +
+	"breaking changes using the following command:\n\n" +
+	"deck convert --from kong-gateway-2.x --to kong-gateway-3.x\n\n" +
+	"This command performs the following changes:\n" +
+	"  - upgrade the `_format_version` value to `3.0`\n" +
+	"  - add the `~` prefix to all routes' paths containing a regex-pattern\n\n" +
+	"These changes may not be correct or exhaustive enough.\n" +
+	"It is strongly recommended to perform a manual audit\n" +
+	"of the updated configuration file before applying\n" +
+	"the configuration in production. Incorrect changes will result in\n" +
+	"unintended traffic routing by Kong Gateway.\n\n" +
+
+	"For more information about this and related changes,\n" +
+	"please visit: https://docs.konghq.com/deck/latest/3.0-upgrade\n\n"
+
 // IsPathRegexLike checks if a path string contains a regex pattern.
 func IsPathRegexLike(path string) bool {
 	return pathRegexPattern.MatchString(path)
@@ -190,27 +205,29 @@ func ConfigFilesInDir(dir string) ([]string, error) {
 	return res, nil
 }
 
-// CheckRoutePaths300AndAbove checks routes' paths format and prints out
-// a warning if regex-like patters without the '~' prefix are found.
-func CheckRoutePaths300AndAbove(route kong.Route) {
-	pathsWarnings := []string{}
+// HasPathsWithRegex300AndAbove checks routes' paths format and returns true
+// if these math a regex-pattern without a '~' prefix.
+func HasPathsWithRegex300AndAbove(route kong.Route) bool {
 	for _, p := range route.Paths {
 		if strings.HasPrefix(*p, "~/") || !IsPathRegexLike(*p) {
 			continue
 		}
-		pathsWarnings = append(pathsWarnings, *p)
+		return true
 	}
-	if len(pathsWarnings) > 0 {
-		cprint.UpdatePrintf(
-			"In Route '%s', a path with regular expression was detected.\n"+
-				"In Kong Gateway versions 3.0 and above, all paths that use regular expressions \n"+
-				"must be prefixed with a ~ character. Without the ~ prefix, regular expression \n"+
-				"based paths will not be matched and processed correctly. \n\n"+
-				"Please run the following command to upgrade your config: \n\n"+
-				"deck convert --from kong-gateway-2.x --to kong-gateway-3.x "+
-				"--input-file <config-file> --output-file <new-config-file>\n\n"+
-				"Please refer to the following document for further details:\n"+
-				"https://docs.konghq.com/deck/latest/3.0-upgrade.\n\n",
-			*route.ID)
+	return false
+}
+
+// PrintRouteRegexWarning prints out a warning about 3.x routes' path usage.
+func PrintRouteRegexWarning(unsupportedRoutes []string) {
+	unsupportedRoutesLen := len(unsupportedRoutes)
+	// do not consider more than 10 sample routes to print out.
+	if unsupportedRoutesLen > 10 {
+		unsupportedRoutes = unsupportedRoutes[:10]
 	}
+	cprint.UpdatePrintf(
+		"%d unsupported routes' paths format with Kong version 3.0\n"+
+			"or above were detected. Some of these routes are (not an exhaustive list):\n\n"+
+			"%s\n\n"+UpgradeMessage,
+		unsupportedRoutesLen, strings.Join(unsupportedRoutes, "\n"),
+	)
 }
diff --git a/validate/validate.go b/validate/validate.go
index cc95c91f7..939549229 100644
--- a/validate/validate.go
+++ b/validate/validate.go
@@ -186,7 +186,13 @@ func (v *Validator) Validate(kongVersion semver.Version) []error {
 
 func validate3xRoutes(routes *state.RoutesCollection) {
 	results, _ := routes.GetAll()
+	unsupportedRoutes := []string{}
 	for _, r := range results {
-		utils.CheckRoutePaths300AndAbove(r.Route)
+		if utils.HasPathsWithRegex300AndAbove(r.Route) {
+			unsupportedRoutes = append(unsupportedRoutes, *r.Route.ID)
+		}
+	}
+	if len(unsupportedRoutes) > 0 {
+		utils.PrintRouteRegexWarning(unsupportedRoutes)
 	}
 }