I have a warning about cacao nibs. The longer you leave them in, the more citrus-y your beer will be. It goes quickly and to the point I may not do that again. If I want chocolate character from nibs, I add them to the mash, and if I want more I have them in the boil.
At 24 hours, my beer was chocolaty, great body, good base on the beer itself which as a porter. There was a hint of citrus there that was quite good. I let it rest overnight at room temp and sampled the next morning. It had a grapefruit aroma and taste that clashed with the porter.
I read about this and thought I was surely safe to leave the nibs in another half day but not so much.