In my case, 485 was approved on Nov 20, 2002.
I checked the online status in the morning on Nov 20. It was
already updated. Then I checked the AVM in the afternoon, it
was updated too.
In case you are interested, your online status after approval
would say something like this
"This case has been approved. On November 20, 2002, an approval notice was mailed. If 14 days have passed and you have not received this notice, you may wish to verify or update your address. To update your address, please speak to an Immigration Information Officer during business hours."
Regards
ssp_aks