Same Stuff Different Day - or:
Same shit, different day.
the acronym is build by the repetition of the "2" meaning "second" as repetition of the previous.
This is mostly used to out that there seems no end to the awkward situation. Yes, there is another new day, but the sore lingers on. Also boring work can have somebody say this.
"yesterday we had a shitty day at work. I come back and you know, s2d2"