[bugs] Wrong date displayed

Hello,

I've noticed that the October has two days with date 27th
Oct 2019. This is how my calendar in calcurse looks like:

         October 2019        
Mon Tue Wed Thu Fri Sat Sun 
30  1   2   3   4   5   6 
7   8   9   10  11  12  13 
14  15  16  17  18  19  20 
21  22  23  24  25  26  27* 
27* 28  29  30  31  1   2 

At the begining I thought that this is because of my Polish locales, but
it is the same when I launch calcurse prefixed with LC_ALL=en_US.UTF-8.

Is this something that you consider as a bug? If not, just let me know.
I use calcurse 4.5.0 on Arch Linux.
I checked on my Raspbery Pi running Raspbian. I have calcurse 4.2.1 there and October is
displayed corretly. 

Best regards,
Szymon

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