AD Connect group/ou filtering question

Hi, I have recently installed AD connect to sync a single OU and have included an AD group.

I have added a number of users to the group and have successfully synced them to 365.

If I now want to remove the group and sync the entire OU, can I just go into the AD connect setup and take out the group filtering option? (leaving just the OU selected)

The OU where the synced user accounts are is currently selected to sync, so I would hope that if I take out the group filter, it will keep them synced because the users are still a member of the selected OU.

thought i would ask here as I dont want want those 365 accounts to be deleted.

Thanks