On-premise email contentious sync to Office 365

Question

i know cut over migration can keep sync the mailbox to office 365 until i change the MX record. but that will sync all the mailboxs of the on-premise exchange. i just want to sync part of the users like 100 out of 1000 to office 365.( about 400gb ). I want to sync them all to office 365 , then cut over. is it possible ?

stage migration is not an option because it will move user one by one. the user cannot update email on the on-premise server. it will take days or weeks to do so. I want to cut over on the same date, so i can make a backup of the cut off day

Answer 1

Could you clarify? Are you syncing ALL users, but in stages of 100 per batch job? Or just 100 out of you total 1000?

You can't sync a subset, then cut over, and then sync another subset.

You can sync a subset by making the migration job, then deleting the users you don't want to sync after they are automatically provisioned, the batch job will fail for those users, but will succeed for the others.