ESA50 - When Is It Posted To Me?

I've been on the ESA assessment rate since January 23'rd. When roughly, is the ESA50 sent to me?

I have obtained medical evidence, and have support letters from my GP and Consultant confirming my limited capability for work.

I'm all ready for the battle that lays ahead. So just wondering when I can expect the ESA50 to land on my doormat.