Calamity's Wake is a card from the Brothers' War set that has the text “Exile Calamity's Wake.” at the end of it.
The clear intention of this card is that after it is cast, it goes to exile instead of the graveyard. However, I'm curious about the wording because it isn't worded as a replacement effect, which means there doesn't seem to be anything stopping this card from going to the graveyard as part of resolution.
The relevant comprehensive rules are:
608.2k If an instant spell, sorcery spell, or ability that can legally resolve leaves the stack once it starts to resolve, it will continue to resolve fully.
608.2m As the final part of an instant or sorcery spell’s resolution, the spell is put into its owner’s graveyard. As the final part of an ability’s resolution, the ability is removed from the stack and ceases to exist.
These two rules together suggest to me that Calamity's Wake exiles itself, continues resolving, then moves to the final steps of resolution which according to 608.2m moves the spell to the owner's graveyard. Nothing about 608.2m looks like it requires the spell to currently be on the stack to happen.
Is there any other comprehensive rule that clears up how a spell exiling itself is supposed to behave? I know how it's clearly meant to work, but I'm just looking for the justification from the comprehensive rules.