Doesnt the purchasers email address have to match the email address on City account?? I am sure that has been said a few times on thread. So you would need to give your uefa log in details to person usng, which is fine if its family of close friend but most would give that access to a random or someone you dont know well. And you have to keep one ticket in the purchasers account according to people I know who went to Euros and a couple of Liverpool fans I know that went last season. So if you have bought 6 tickets you can only transfer 5 to others.
We probably wont know what actually happens til we get tickets next week, but some who have used others codes might have issues???