diff --git a/doc/BUILDING.md b/doc/BUILDING.md
index cb33450..60fd65c 100644
--- a/doc/BUILDING.md
+++ b/doc/BUILDING.md
@@ -9,9 +9,9 @@ systems.
 
 aprsc has been built and tested on:
 
-* Ubuntu LTS (12.04, 14.04, 16.04): i386 and x86_64
-* Debian 7.0, "wheezy": i386 and x86_64
-* Debian 8.0, "jessie": i386 and x86_64
+* Ubuntu LTS (18.04, 20.04): x86_64
+* Debian 9.0, "stretch": i386 and x86_64
+* Debian 10.0, "buster": i386 and x86_64
 * Mac OS X 10.8 (Snow Leopard): x86
 * FreeBSD 8.2 and 9.0 on amd64, 7.2 on i386
 * Solaris 11 (SunOS 5.11 11.0 i86pc i386)
diff --git a/doc/INSTALLING.md b/doc/INSTALLING.md
index 49698ae..44bd6a0 100644
--- a/doc/INSTALLING.md
+++ b/doc/INSTALLING.md
@@ -7,7 +7,6 @@ aprsc is "officially" "supported" on the following platforms:
 * Debian stable (10.0, "buster"): i386, x86_64
 * Debian oldstable (9.0, "stretch"): i386, x86_64
 * Ubuntu LTS (18.04, 20.04): i386 and x86_64
-* CentOS 6: i386 and x86_64
 * CentOS 7: x86_64
 
 The i386 builds actually require an i686 (Pentium 2 class) CPU or