Emphasize that already-available authenticators also "become available"

index.bs

@@ -877,7 +877,7 @@ When this method is invoked, the user agent MUST execute the following algorithm
 
     Note: What qualifies an [=authenticator=] as "available" is intentionally unspecified; this is meant to represent how
     [=authenticators=] can be hot-plugged into (e.g., via USB) or discovered (e.g., via NFC or Bluetooth) by the [=client=] by
-    various mechanisms.
+    various mechanisms, or permanently built into the [=client=].
 
 1. Start |lifetimeTimer|.
 
@@ -895,7 +895,9 @@ When this method is invoked, the user agent MUST execute the following algorithm
             whose name is "{{AbortError}}" and terminate this algorithm.
 
         :   If an |authenticator| becomes available on this platform,
-        ::  1. If <code>|options|.{{PublicKeyCredentialCreationOptions/authenticatorSelection}}</code> is [=present=]:
+        ::  Note: This includes if the |authenticator| was initially available when |lifetimeTimer| started.
+
+            1. If <code>|options|.{{PublicKeyCredentialCreationOptions/authenticatorSelection}}</code> is [=present=]:
 
                   1. If <code>|options|.{{PublicKeyCredentialCreationOptions/authenticatorSelection}}.{{authenticatorAttachment}}</code> is
                     [=present|present=] and its value is not equal to |authenticator|'s attachment modality, [=iteration/continue=].
@@ -1210,7 +1212,7 @@ When this method is invoked, the user agent MUST execute the following algorithm
 
     Note: What qualifies an [=authenticator=] as "available" is intentionally unspecified; this is meant to represent how
     [=authenticators=] can be hot-plugged into (e.g., via USB) or discovered (e.g., via NFC or Bluetooth) by the [=client=] by
-    various mechanisms.
+    various mechanisms, or permanently built into the [=client=].
 
 1. Start |lifetimeTimer|.
 
@@ -1230,7 +1232,9 @@ When this method is invoked, the user agent MUST execute the following algorithm
             return a {{DOMException}} whose name is "{{AbortError}}" and terminate this algorithm.
 
         :   If an |authenticator| becomes available on this platform,
-        ::  1. If <code>|options|.{{PublicKeyCredentialRequestOptions/userVerification}}</code> is set to
+        ::  Note: This includes if the |authenticator| was initially available when |lifetimeTimer| started.
+
+            1. If <code>|options|.{{PublicKeyCredentialRequestOptions/userVerification}}</code> is set to
                 {{UserVerificationRequirement/required}} and the |authenticator| is not capable of performing [=user verification=],
                 [=iteration/continue=].