I recently migrated to the new email settings and everything was fine. I have an iPhone 5 c and updated to ios9 and still was fine. Now all of a sudden I first could not send mail and in working on that I now can not receive mail. I have a Wildblue account.
First of all make you you are on update 9.0.1 for your iOS, there were many issues with 9.0 and many people including my boss had there phone crash. Secondly if you can still login online and access your email then go back through your phone and make sure the port setting and everything match up with the settings here