Closes #14267: Merged fix from 3.2.

diff --cc Lib/logging/handlers.py
index ee0096a8cb79ae16fe3be6eb481d47d0ec1ed717,73ce031545d9727c662bbeb0ea6ec6a5cb1bfd31..bebd79a8fe1e139c6bb5540586f8523c69a1100d
--- 1/Lib/logging/handlers.py
--- 2/Lib/logging/handlers.py
+++ b/Lib/logging/handlers.py
@@@ -363,11 -331,17 +366,18 @@@ class TimedRotatingFileHandler(BaseRota
              timeTuple = time.gmtime(t)
          else:
              timeTuple = time.localtime(t)
 -        dfn = self.baseFilename + "." + time.strftime(self.suffix, timeTuple)
+             dstThen = timeTuple[-1]
+             if dstNow != dstThen:
+                 if dstNow:
+                     addend = 3600
+                 else:
+                     addend = -3600
+                 timeTuple = time.localtime(t + addend)
 +        dfn = self.rotation_filename(self.baseFilename + "." +
 +                                     time.strftime(self.suffix, timeTuple))
          if os.path.exists(dfn):
              os.remove(dfn)
 -        os.rename(self.baseFilename, dfn)
 +        self.rotate(self.baseFilename, dfn)
          if self.backupCount > 0:
              for s in self.getFilesToDelete():
                  os.remove(s)