According to the standard Shas print (Vilna Bavli), the order of Masechtas is Pesachim-Shekalim-Rosh Hashana-Yoma-Sukka-Beitza. This makes (some) sense as this is the order of holidays.
However, the Bavli Daf Yomi schedule is Pesachim-Shekalim-Yoma-Sukkah-Beitza-Rosh Hashana-Taanis. I note Daf Yomi was instituted after the Vilna print.
Why is there a discrepancy in the order?