A Voice that comes on, saying it's "transferring" (or a beep); When someone calls after the first 30 Sec. "transferring" notification sounds (or a beep,beep,beep as an in-between ring of silence or 1/2¿) then transfers to the FollowMe #. So when people are calling they know whats going on a bit and don't hang up so soon.
People are use to the bell 4-6 rings to voicemail but 30 + 70 sec might be a little to long for the callers before giving up.