diff --git a/flake.nix b/flake.nix
index 9ceb5dd..6b02763 100644
--- a/flake.nix
+++ b/flake.nix
@@ -169,17 +169,18 @@
               };
 
               # Auto-upgrade: pulls latest flake and runs nixos-rebuild switch.
-              # NOTE: this branch (dev) pins the upgrade source to ?ref=dev so
-              # any ATM flashed from `dev` stays on `dev`. Without the explicit
-              # ref, nix would resolve to the repo's default branch (main),
-              # which would silently regress a dev-deployed Sintra back to the
-              # lamassu-next production code at 04:00. The `main` branch's
-              # flake.nix continues to omit ?ref= so production ATMs (batm3,
-              # douro) keep pulling main HEAD as before.
-              # To update manually: sudo nixos-rebuild switch --flake git+ssh://forgejo@git.atitlan.io/aiolabs/lamassu-next.git?ref=dev#<model>-installed
+              # NOTE: bitSpire machines pull from the `aiolabs/bitspire` repo —
+              # the post-migration home of this code. This branch (dev) pins the
+              # upgrade source to ?ref=dev so any ATM flashed from `dev` stays on
+              # `dev`. Without the explicit ?ref=dev, nix would resolve the repo's
+              # default branch and could silently change a dev-deployed Sintra at
+              # 04:00. The legacy `aiolabs/lamassu-next` repo still feeds the
+              # not-yet-converted production ATMs (batm3, douro) from its own
+              # branches; it is retired once those machines migrate to bitspire.
+              # To update manually: sudo nixos-rebuild switch --flake git+ssh://forgejo@git.atitlan.io/aiolabs/bitspire.git?ref=dev#<model>-installed
               system.autoUpgrade = {
                 enable = true;
-                flake = "git+ssh://forgejo@git.atitlan.io/aiolabs/lamassu-next.git?ref=dev#${machineModel}-installed";
+                flake = "git+ssh://forgejo@git.atitlan.io/aiolabs/bitspire.git?ref=dev#${machineModel}-installed";
                 flags = [ "--refresh" ];
                 dates = "04:00"; # daily at 4am
                 allowReboot = false;