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

202620262026202620262026
FebMarAprMayJunJul
      
We1We1We
Th2Th2Th
Fr3Fr13Fr
Sa4Sa24Sa
Su115Su35Su
      
Mo226Mo416Mo
Tu337Tu527Tu
We448We638We
Th559Th749Th
Fr6610Fr8510Fr
Sa7711Sa9611Sa
Su8812Su10712Su
      
Mo9913Mo11813Mo
Tu101014Tu12914Tu
We111115We131015We
Th121216Th141116Th
Fr131317Fr151217Fr
Sa141418Sa161318Sa
Su151519Su171419Su
      
Mo161620Mo181520Mo
Tu171721Tu191621Tu
We181822We201722We
Th191923Th211823Th
Fr202024Fr221924Fr
Sa212125Sa232025Sa
Su222226Su242126Su
      
Mo232327Mo252227Mo
Tu242428Tu262328Tu
We252529We272429We
Th262630Th282530Th
Fr2727Fr292631Fr
Sa2828Sa3027Sa
Su29Su3128Su
      
Mo30Mo29Mo
Tu31Tu30Tu

35 rows

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