"Six and a half"

3 days – is that a quick turnaround?

Basically, yes. One day to simply admire the map and understand the connections between the zones. Another day to play through it somehow, assessing the most likely routes and the most challenging battles. Another day to create a walkthrough, already with the excavation of the most likely heroes. Another day to think about what could be improved to fit within the "golden rule." And another day to finalize the walkthrough. Something like that.
Of course, a day isn't 24 hours :)

From what I said, it's clear that I managed to do it in three days :)