Re: Has there ever been a February 30th? If not, why not. If so, when was it?

Greetings, Susan:

Let me start this Answer by referring you to this Web page: 
http://webexhibits.org/calendars/calendar-christian.html

It contains a great deal of apparently objective information
about the early history of the Christian calendar.  Most
relevant to your Question is this portion:

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Occasionally one reads the following story:

"Julius Caesar made all odd numbered months 31 days long,
and all even numbered months 30 days long (with February
having 29 days in non-leap years). In 44 B.C.E. Quintilis
was renamed 'Julius' (July) in honor of Julius Caesar, and
in 8 B.C.E. Sextilis became 'Augustus' in honor of emperor
Augustus.  When Augustus had a month named after him, he
wanted his month to be a full 31 days long, so he removed
a day from February and shifted the length of the other
months so that August would have 31 days."

This story, however, has no basis in actual fact. It is a
fabrication possibly dating back to the 14th century.

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(Note, B.C.E. is "Before the Christian Era".  Some people
say that the C. means "Common", but the Christian calendar
is not globally common, a fact made plain by other Web
pages at that site.)

If the preceding STORY is true, then it could be that for
just a few years, between the reigns of Julius and Augustus
Caesar, February might have had 30 days.  But since that
story is being strenuously denied in the main article, due
to lack of facts, I'm willing consider the it to be just a
rumor (for now).  Certainly I completely agree that there
has not recently been, nor will there be in the future of
the current Christian Calendar, a 30-day February.

I'm reasonbly sure I'm qualified to state such agreement
because during 1998, I spent a fair amount of time working
on the computer software issue that was widely known as
"The Y2K Problem".  There were actually two aspects to that
problem.  (1) Much old computer software was written to
accommodate 2-digit years:  When a year was stated to be
76, everyone could assume it meant 1976.  That assumption
was no longer acceptable as the year 2000 approached.
(2) The modern Gregorian version of the Julian calendar,
as adopted by Christianity, does not automatically decree
every fourth year to be a leap year (in which February is
given its 29th day).  This is because (as the article
noted) such a decree causes the calendar to count one
extra day, over a 128-year period, than actually occurs
during 128 years.  Because the Gregorian calendar is a
little more complex than the Julian calendar, computer
programs that were modified for Y2K were usually also
modified to correctly compute Gregorian leap years.
I was doing exactly that, and so can explain it here:

In the Gregorian system, every 100th year is NOT a leap
year.  February only has 28 days in century-years such
as 1700, 1800, and 1900.  However, every 400th year IS
a leap year, and so 2000 was a leap year, with the usual
29-day February.  (If you bought a digital watch prior to
2000, you may recall the documentation bragging about how
its calendar would keep track of dates until the year
2100.  This was simply luck, that the manufacturers of
such watches could take advantage of every-fourth-year
being a leap year, between 1900 and 2100.)

I submit that your patron once encountered an explanation
of how Gregorian leap years are computed, but then either
misintepreted or misremembered part of it, when discussing
it with you.

In closing, I'll just say that the Gregorian calendar is
quite adequate for more than a thousand years into the
future.  Instead of gaining a day every 128 years, it
gains a day every 3323 years.  Probably Somebody Will
Decide to drop one of those every-400th-year leap years.
Certainly we don't have to worry about it now....