diff --git a/architecture-docs/data-model-requirements.md b/architecture-docs/data-model-requirements.md
index 6c50ffb..df79b44 100644
--- a/architecture-docs/data-model-requirements.md
+++ b/architecture-docs/data-model-requirements.md
@@ -43,6 +43,7 @@ FooUniversity (Operator)
            * may need to rewrite URLs to blobs automatically, depending on the underlying URL scheme, which may be per setup or application
         * limits? per application? per user? where are these used/set/enforced?
         * TODO: what does e.g. borgmatic need to back up?
+          * note that selfhostblocks may already have some of the needed info here
           * complications: in case details such as connections change, those may need adjusting, implying application-specification reconfiguring
             * potentially propagate thru by e.g. TF?
         * out of scope?: focus on actual state, disregarding reconstructable stuff