First column:   year   month .   Number of months
Repeat day codes every columns.   Entry padding em.  

202620262026202620262026
MarAprMayJunJulAug
      
We1We1We
Th2Th2Th
Fr31Fr3Fr
Sa42Sa41Sa
Su153Su52Su
      
Mo264Mo163Mo
Tu375Tu274Tu
We486We385We
Th597Th496Th
Fr6108Fr5107Fr
Sa7119Sa6118Sa
Su81210Su7129Su
      
Mo91311Mo81310Mo
Tu101412Tu91411Tu
We111513We101512We
Th121614Th111613Th
Fr131715Fr121714Fr
Sa141816Sa131815Sa
Su151917Su141916Su
      
Mo162018Mo152017Mo
Tu172119Tu162118Tu
We182220We172219We
Th192321Th182320Th
Fr202422Fr192421Fr
Sa212523Sa202522Sa
Su222624Su212623Su
      
Mo232725Mo222724Mo
Tu242826Tu232825Tu
We252927We242926We
Th263028Th253027Th
Fr2729Fr263128Fr
Sa2830Sa2729Sa
Su2931Su2830Su
      
Mo30Mo2931Mo
Tu31Tu30Tu

35 rows

Notes on curious non-bug on my home machine:
with date_default_timezone_set('UTC') - be patient
without that declaration