Yes, inmates in the SHU are only eligible to get and send mail. The mail is delivered on a normal schedule. They are allowed ONE 15-minute phone call per week.
https://www.inmateaid.com/ask-the-inmate/can-an-inmate-in-shu-receive-mail-how-long-does-it-take-for-them-to-receive-it#answer
Accepted Answer Date Created: May 31,2019