"Encyclopaedist" and "Herodotus' disciple" achievements randomly popping up

[Bartolomeo Coglione]

Yesterday after losing a run i noticed that these 2 achievements randomly appeared out of nowhere. Please note that i've played only 4.5 hours and i have yet to complete a single run. The furthest i got to is to Ephestus and i died. During the run i didn't even notice that those 2 achievemnt popped up and, based from the achievement's description, i should have completed the Encyclopedia to unlock it and unlock and use every hero. After finishing the run and checking the Atlaatnis achievement, these 2 were there.
Can someone explain if this is just a bug or if i am reading the achievement's description wrong?
Thanks :)

[Takumashii]

Almost certainly a bug.

This happened to me as well - I've launched the game three times since coming back to it, and it came up the third time. They popped after I saved and quit a run in which I got my first secret boss, but that's the only notable thing that happened.

[Doppledumb]

I don't know if a dev still watch this forum but I've just had the exact same thing happening to me while starting the game

[Kokoloko]

Had the same thing happen to me today, with less than 6 hours of playtime and probably around ~20% of total game progress at best.