diff --git a/src/names/project.go b/src/names/project.go
index 39ab9b5..51457b1 100644
--- a/src/names/project.go
+++ b/src/names/project.go
@@ -12,7 +12,6 @@ var ErrInvalidProjectName = errors.New("invalid project name")
 var ErrInvalidProjectURL = errors.New("invalid project URL")
 
 const indexProject = ".index"
-const previewSeparator = "@"
 
 // Name of a git-pages project. The index project corresponds to the root URL of a domain, and
 // non-index projects are distinguished by the first path segment of the URL.
@@ -49,13 +48,13 @@ func (p Project) IsIndex() bool {
 // a preview project name for a pull request. In the latter case, prNumber is set correspondingly,
 // and baseName contains the repository name. Otherwise, baseName equals p.String().
 func (p Project) GetPullRequest() (baseName string, prNumber int64, isPreview bool) {
-	var atSuffix string
-	if baseName, atSuffix, isPreview = strings.Cut(p.String(), "@"); isPreview {
-		prNumber, _ = strconv.ParseInt(atSuffix, 10, 64)
-	} else {
-		baseName = p.String()
+	if repoName, atSuffix, isPreview := strings.Cut(p.String(), "@"); isPreview {
+		if prNumber, err := strconv.ParseInt(atSuffix, 10, 64); err == nil && prNumber > 0 {
+			baseName = repoName
+			return repoName, prNumber, true
+		}
 	}
-	return
+	return p.String(), 0, false
 }
 
 func validateProjectName(name string) (proj Project, err error) {
@@ -70,21 +69,6 @@ func validateProjectName(name string) (proj Project, err error) {
 		return
 	}
 
-	if strings.Count(name, previewSeparator) > 1 {
-		err = fmt.Errorf("%w: must contain at most one %q", ErrInvalidProjectName, previewSeparator)
-		return
-	}
-
-	if _, atSuffix, isPreview := strings.Cut(name, "@"); isPreview {
-		if prNumber, parseErr := strconv.ParseInt(atSuffix, 10, 64); parseErr != nil {
-			err = fmt.Errorf("%w: malformed pull request number", ErrInvalidProjectName)
-			return
-		} else if prNumber <= 0 {
-			err = fmt.Errorf("%w: malformed pull request number", ErrInvalidProjectName)
-			return
-		}
-	}
-
 	proj.name = name
 	return
 }
diff --git a/src/names/project_test.go b/src/names/project_test.go
index b318dba..16fe87f 100644
--- a/src/names/project_test.go
+++ b/src/names/project_test.go
@@ -58,10 +58,6 @@ func TestParseProjectName(t *testing.T) {
 	checkErr(t, ParseProjectName, "meow\\miau", ErrInvalidProjectName)
 	checkErr(t, ParseProjectName, "meow%miau", ErrInvalidProjectName)
 	checkErr(t, ParseProjectName, "meow*", ErrInvalidProjectName)
-	checkErr(t, ParseProjectName, "foo@10@11", ErrInvalidProjectName)
-	checkErr(t, ParseProjectName, "foo@awa", ErrInvalidProjectName)
-	checkErr(t, ParseProjectName, "foo@0", ErrInvalidProjectName)
-	checkErr(t, ParseProjectName, "foo@-10", ErrInvalidProjectName)
 }
 
 func TestParseProjectURL(t *testing.T) {
@@ -97,6 +93,26 @@ func TestProjectProperties(t *testing.T) {
 	checkEq(t, prNumber, 0)
 	checkEq(t, isPreview, false)
 
+	baseName, prNumber, isPreview = Project{"foo@10@11"}.GetPullRequest()
+	checkEq(t, baseName, "foo@10@11")
+	checkEq(t, prNumber, 0)
+	checkEq(t, isPreview, false)
+
+	baseName, prNumber, isPreview = Project{"foo@-1"}.GetPullRequest()
+	checkEq(t, baseName, "foo@-1")
+	checkEq(t, prNumber, 0)
+	checkEq(t, isPreview, false)
+
+	baseName, prNumber, isPreview = Project{"foo@0"}.GetPullRequest()
+	checkEq(t, baseName, "foo@0")
+	checkEq(t, prNumber, 0)
+	checkEq(t, isPreview, false)
+
+	baseName, prNumber, isPreview = Project{"foo@meow"}.GetPullRequest()
+	checkEq(t, baseName, "foo@meow")
+	checkEq(t, prNumber, 0)
+	checkEq(t, isPreview, false)
+
 	baseName, prNumber, isPreview = Project{"foo@10"}.GetPullRequest()
 	checkEq(t, baseName, "foo")
 	checkEq(t, prNumber, 10)