Forum:Flipped face up

How do effects similar to Fossil Dina and Snowman Eater work? Monsters are flipped in sub-step 3 of the damage step. Because it is flipped up and not a flip effect would the effect trigger in sub-step 3 or sub-step 5/6. If similar effects do trigger in sub 3 would snowman eater destroy the attacking monster before being destroyed assuming that the attacking monster is stronger.