Hypothetical Tournament Ruling Question

[Double Ice]

Just wanted to know about this, I couldn't find it anywhere.

Say I have K high and my opponent has A high on the river. I bet and he calls. I table my hand. A high mucks facedown but the cards are identifiable. A couple seconds later as the pot is moving in my direction, he says "Oh, I have A high, turn up the cards." The floor is called.

What is the ruling?

Does the ruling change if
[*](a)my bet on the river was all-in[*](b)I miscalled my hand? (say I said "two pair" while tabling.)[*](a) and (b)