Oddity in calendar output

[Carl Johnson]

I just realized that one calendar(1) entry seems to be notifying me in
the wrong week.  I have a calendar entry: 
     September SatSecond     Shrewsbury Fair (2 days)
in my ~/calendar file to notify me on the second Saturday, but it
notified me on the first Saturday.  I get the following results:
     $ calendar -t 07-09-2019
     Sep  7* Shrewsbury Fair (2 days)
     $ calendar -t 14-09-2019
     $
September 7 is clearly the first Saturday, so why does it think that it
is the second Saturday and the 14th is not?  I also tried changing
'SatSecond' to 'Sat+2', but that gives the same result.

Am I missing something obvious, or should I file a PR on this?  Thanks
for any suggestions.

P.S.  Look at shrewfaire.com if you want to know what Shrewsbury Fair
is.

-- 
Carl Johnson		carlj at peak.org