diff --git a/book.toml b/book.toml
index 8d5f2afa4..88b2cb7de 100644
--- a/book.toml
+++ b/book.toml
@@ -26,4 +26,4 @@ git-repository-url = "https://github.com/element-hq/matrix-authentication-servic
 site-url = "/matrix-authentication-service/"
 
 [output.html.redirect]
-"/as-login.html" = "setup/migration.html#encrypted-bridges-need-msc4190-support"
+"/as-login.html" = "setup/migration.html#encrypted-bridges-need-application-service-device-management-support"
diff --git a/docs/setup/migration.md b/docs/setup/migration.md
index 3aa7e8d0c..6a906039b 100644
--- a/docs/setup/migration.md
+++ b/docs/setup/migration.md
@@ -30,12 +30,12 @@ If your Synapse homeserver currently uses a custom password provider module, ple
 It is worth noting that MAS currently only supports PostgreSQL as a database backend.
 The migration tool only supports reading from PostgreSQL for the Synapse database as well.
 
-#### Encrypted bridges need MSC4190 support
+#### Encrypted bridges need application service device management support
 
 Application services used to log in through the legacy `m.login.application_service` login type to create encryption-capable devices for their users.
-This login type is not available once authentication is delegated to MAS: encrypted bridges must instead create devices through the [device management endpoints](https://spec.matrix.org/v1.19/application-service-api/#device-management) introduced by [MSC4190](https://github.com/matrix-org/matrix-spec-proposals/pull/4190).
+This login type is not available once authentication is delegated to MAS: encrypted bridges must instead create devices through the [device management endpoints](https://spec.matrix.org/v1.19/application-service-api/#device-management) of the Application Service API (MSC4190), available since Matrix 1.17.
 
-This requires Synapse 1.141.0 or later, and a bridge which implements MSC4190.
+This requires Synapse 1.141.0 or later, and a bridge which implements these endpoints.
 mautrix-based bridges do, with the `encryption.msc4190` option; see [their documentation](https://docs.mau.fi/bridges/general/end-to-bridge-encryption.html#use-with-next-gen-auth-oauth-mas-msc4190).
 For other bridges, check with their author.