Perhaps I should mention again, the order of troops to be released could change at any time, and that is especially true for the coming mythics - the release order of Euryali, Infernus and Yasmine’s Chosen was switched around a few times already, and is not unlikely to change again.
Also, while my usual source of troop release schedule shows Euryali to be next, I found another source that shows Infernus as the next mythic. I don’t know which is correct, so unless a dev confirms one of those, assume it could be either.