We, too, are sailing the Magica on Jan 21st!! I can not pull up the excursions on Costa.
I get a page that reads 'shore excursions' but no info below. I've even gone onto Carnival, etc, to look at the excursions assuming they would be about the same. Wanted to do the Rainforest but it too closes at 6pm. Well, still have a few months to figure it out... thanks for your help