There isn't an outcome to appeal yet - what would CAS be involved for?
The club did ask (reportedly) about the process, but my understanding is that CAS won't be able to rule on anything unfinalised.
City involved CAS on the question of the legality of the Email, if CAS do not allow it UEFA are stuffed, so CAS dodged a reply now UEFA are in limbo the hard liners Tobias and Bayern want it to go through, but others look at the cost, as City now know they will take the case else where, which will cast a huge slur on CAS`s impartiality