I hate to be the voice of doubt but I really don't see things being back to normal by September. Until there's a vaccine, Disney Parks are going to be severely impacted. If the parks are even open in September they'll be severely compromised with reduced attractions, shorter opening hours and no parades / fireworks as Disney will be financially hurting big time. Any cost they can cut, they will and it's hard to blame them. They may even need to reduce park admissions as there won't be a vaccine by then so social distancing will still be required and they'll need to be extra vigilant with cleaning surfaces, etc. If an outbreak was to happen and be linked back to Disney, it would be a disaster for them so they'll be doing everything they think they need to do to eliminate that risk.
I really hope I'm wrong but I don't see it.