Yes you can. But that does not mean you do not need to adjust the config. For istance, private- versus public numbering needs attentention for it is changed since R7. In all my projects I do a test migration first, just to see if the xln will load. When that works that step of the migration is confirmed. During the actual Go Live, make sure you have a solid testplan and let the customer execute it. So test Fax, modem, call center, attendant, etc. and also check if names and numbers are sent correctly. Saving and transferring security settings is i my opinion not a good idea but is possible.
Freelance Certified Avaya Aura Engineer