Mail continues even during lockdown. Federal prison camps are not "terrible" when it comes to prison life, even during a lockdown. Most probably visitation is suspended and maybe phone privileges or commissary. There must have been some rules violation that is creating this mass punishment but in the camps, they rarely last a long time.
https://www.inmateaid.com/ask-the-inmate/if-the-federal-prison-camp-is-in-lockdown-do-they-still-allow-mail-my-fiance-says-that-they-do-have-to-allow-personal-mail#answer
Accepted Answer Date Created: June 30,2013