Migrate CIX and SGN installed workstation to new domain


Our organization using both Sophos Central managed endpoints and Safeguard Encryption for up to 500 workstations. 

We have a request from management to migrate from the old domain to the new domain. Can I get any advice on the best method to perform this migration? 

1) SGN management server I guess we need to reinstall? or just change organization?

2) Do the encrypted workstation need to be decrypted before joining the new domain and encrypt again?

3) How about the endpoint? do we have to reinstall? I guess central will automatically detect the User Account right?