--- a/doc/installation.txt	Tue Oct 10 20:33:22 2023 -0400
+++ b/doc/installation.txt	Sun Oct 15 20:56:50 2023 -0400
@@ -1754,11 +1754,13 @@
   by some Python users.
 
 ``--build-arg="source=pip_sdist"``
-  Disabled.
+  Disabled - hopefully it will be available in the future.
   This is meant for maintainer/developer use. It installs using
   pip from a source distribution (sdist) tarball built by
   following the RELEASE.txt. It is meant for testing
-  releases. Normal users/admins should not use it.
+  releases or building a docker image that installs a new pending
+  source distribution release. Normal users/admins should not use it.
+  Use ``local`` or ``pip_local`` instead.
 
 Build a docker container using the code in the current directory,
 with this build command from the top of the source tree::