ADC for Exchange 5.5 to Exchange 2000

I have recently upgraded from Exchange 5.5 to 2000 on a new mail server. I used the Active Directory Connector (ADC) during the process. Exchange 2000 is up and running. At what point in time can I deactivate the ADC that was used during the upgrade??? I has been 24 hours since the upgrade and so far no complaints.
Thanks for any help!