What tells cyrus to deliver to domain

[Jon <jonr@xxxxxxxxxx>]

I am fighting trying to understand why my mail gets delivered to 
/var/spool/imap/j instead of /var/spool/imap/domain/d/destar.net/j/. I 
had this working but now when I send a message it goes to the former 
rather than the latter. Can someone shed some light on this for me?

Thanks for any help,

Jon