I just recently purchased a AT&T nexus one off of eBay and the original owner did not frequently use the phone, so he never updated from 2.1. So its just EPE54B. I have had the phone for a little over 2 weeks and I have not received a notification to update. Since gingerbread was recently being rolled out, today I tried "checkin", I got a notification for a system update, hit install now, and after the phone was apparently updating, it restarted still running 2.1. The phone is not rooted, and all stock. Could someone please let me know what my problem is? Is froyo necessary in order to get Gingerbread?