Alpha
As it has been pointed out by PAC and SMK, SMOP was not an issue or even a factor. In the case of adjacent screens covering an active sector and under low traffic SMOP is applicable. As it is further common practice (globally) to unman inactive sectors during the night shift the BFU has confirmed that not all WP were staffed, which as I said is common just about with any ANSP.
On this issue however I'd like to understand your knowledge on skyguides SMOP and its night ops implementation.
For as long as you keep trying to lay the blame on skyguide you will have to prove your accusation. "Nulla poena sine culpa"
Thus far you've come a bit short of proof.