remove redundant whatsnew section

Author: Matt Roeschke

doc/source/whatsnew/v0.24.0.txt

@@ -158,38 +158,6 @@ array, but rather an ``ExtensionArray``:
 This is the same behavior as ``Series.values`` for categorical data. See
 :ref:`whatsnew_0240.api_breaking.interval_values` for more.
 
-.. _whatsnew_0240.enhancements.calendarday:
-
-:class:`Day` and associated frequency alias ``'D'`` were documented to represent
-a calendar day; however, arithmetic and operations with :class:`Day` consistently
-respected absolute time (i.e. ```Day(n)`` and acted identically to ```Timedelta(days=n)``).
-
-:class:`CalendarDay` and associated frequency alias ``'CD'`` are now available
-and respect calendar day arithmetic. (:issue:`22274`, :issue:`20596`, :issue:`16980`, :issue:`8774`)
-
-Addition with :class:`CalendarDay` across a daylight savings time transition:
-
-.. ipython:: python
-
-   ts = pd.Timestamp('2016-10-30 00:00:00', tz='Europe/Helsinki')
-   ts + pd.offsets.Day(1)
-   ts + pd.offsets.CalendarDay(1)
-
-However, if the resulting arithmetic results in a non-existent or ambiguous
-time, and error will raise
-
-.. ipython:: python
-
-   Timestamp("2018-11-03 01:00:00", tz='US/Pacific') + CalendarDay(1)
-
-The ``'CD'` frequency alias can be used with :func:`date_range` to create
-a sequence of dates that are separate by a calendar day.
-
-.. ipython:: python
-
-   ts = pd.Timestamp('2016-10-30 00:00:00', tz='Europe/Helsinki')
-   pd.date_range(start=ts, freq='CD', periods=3)
-   pd.date_range(start=ts, freq='D', periods=3)
 
 .. _whatsnew_0240.enhancements.other: