I have been receiving calls asking for Rodney Hill since I got my phone number they went on for the first six months stopped for 3 years and I just received one from this number asking for him.

I got it too. I'm a Tech alum who has contributes every year so the Georgia Tech Alumni Association was probably hitting me up again.

Someone from a 404 area code keeps calling me but never leaves a message. The numbers are the same except the last digit changes.

received several calls without any message

I received one last night at 7:50pm from this number.  The CID said "Georgia Institu".  I have a child at GaTech (Georgia Institute of Technology) so I assumed it was from them.  Not so sure now after reading this thread.

I too receive calls from a variation of the number that begins with 404-894 around 7-7:30 in the evening on weekdays. I've always known the 404-894 prefix to belong to Georgia Tech, because I went there. I discovered these calls at 7-7:30 in the evening are actually from the Georgia Tech Alumni Association seeking roll call donations.