WWE issued the following:

Unfortunately, Dean Ambrose will not be able to appear at the WrestleMania Axxess Premium VIP Autograph Session on Sunday, April 8, at 10 a.m. However, we are pleased to inform the WWE Universe that WWE Hall of Famers Sting and Ric Flair will appear at this Premium VIP Autograph Session. Your existing Dean Ambrose Premium VIP ticket will still grant you access to the Premium VIP Autograph Session on Sunday, April 8, at 10 a.m. with Sting and Flair.