diff --git a/src/uproot/_util.py b/src/uproot/_util.py
index 28ac3665e..1a86c4207 100644
--- a/src/uproot/_util.py
+++ b/src/uproot/_util.py
@@ -435,8 +435,8 @@ def file_path_to_source_class(file_path, options):
         return source_cls, file_path
 
     elif scheme == "s3":
-        # https://github.com/scikit-hep/uproot5/pull/1012
-        source_cls = uproot.source.s3.S3Source
+        # uproot.source.s3.S3Source
+        source_cls = uproot.source.fsspec.FSSpecSource
         return source_cls, file_path
 
     elif scheme in ("http", "https"):
diff --git a/src/uproot/version.py b/src/uproot/version.py
index a395bccc8..dfdb7f2ea 100644
--- a/src/uproot/version.py
+++ b/src/uproot/version.py
@@ -12,7 +12,7 @@
 
 import re
 
-__version__ = "5.1.2"
+__version__ = "5.2.0rc1"
 version = __version__
 version_info = tuple(re.split(r"[-\.]", __version__))