Hi,
We are going to have a Hybrid migration. Our Email domain is same as our external domain name. We have single forest with three domains. USer having UPN as internal domain name. I now understand that i have to add another UPN same our external domain name and associate it with users going to be migrated office 365. Please advice if i am wrong. Our external domain also contain a dash value - ( Eg xxxxhs-edu.sa ) also a public domain .sa value . I read in an article that UPN should not contain dash values.But it is required us to use same email domain for both exchange. Please advice if this will make an issue.
