We're assuming we know the details of Rafael's contract. We do not. That's the whole point. Plus, we do NOT know if Moshiri wants to do a sacking face-to-face, regardless of what the board decide.
If you think there'll be an annoucement at just-gone-midnight Saturday night, I don't know what to tell you. I suspect everyone will meet tomorrow, all the T's crossed and I's dotten (so to speak), then -and only then- will the press be informed.
I think we all know it's hugely unlikely he'll be here for Villa, but that doesn't mean the board need to rush press briefings. Chances are it'll be done Sunday, maybe announced publically tomorrow, maybe Monday. Either way, behind the scenes, Dunc & co will have been told take training. As I said, let's see what tomorrow brings.