Office 365 - Can I keep using the email domain "@ust.hk" or "@stu.ust.hk" when composing message to students who have migrated to @connect service?

Yes. Since all @connect users will have their equivalent @ust.hk (or @stu.ust.hk) email alias same as their HKUST Network ID, you can keep using the existing the email domain "@ust.hk” or "@stu.ust.hk” when addressing to current students no matter they are using the new @connect service or the legacy iMail Service.

As far as the student’s HKUST Network account is valid, the email system will deliver messages to student’s @connect.ust.hk email account automatically no matter you are sending to their @ust.hk (or @stu.ust.hk) email alias, or their @connect email address.

However, when students have completed their courses in HKUST or graduated, their HKUST Network account will be expired and you will need to address to their @connect email address for these Alumni.