diff --git a/src/centpkg/cli.py b/src/centpkg/cli.py
index ad42cda..b571b8d 100755
--- a/src/centpkg/cli.py
+++ b/src/centpkg/cli.py
@@ -205,6 +205,7 @@ class centpkgClient(cliClient):
                     divergent_branch = centpkg.utils.does_divergent_branch_exist(
                                             self.cmd.repo_name,
                                             rhel_version,
+                                            active_y,
                                             rhel_dist_git,
                                             pp_api_url,
                                             "rpms")
diff --git a/src/centpkg/utils.py b/src/centpkg/utils.py
index e17d0d3..e611fd1 100644
--- a/src/centpkg/utils.py
+++ b/src/centpkg/utils.py
@@ -286,17 +286,12 @@ def stream_mapping(csname):
         return "rhel-11"
     return None
 
-def does_divergent_branch_exist(repo_name, rhel_version, rhel_dist_git, pp_api_url, namespace):
+def does_divergent_branch_exist(repo_name, rhel_version, active_y, rhel_dist_git, pp_api_url, namespace):
     logger = logging.getLogger(__name__)
 
     # Determine if the Y-1 branch exists for this repo
 
-    # Look up the Y-1 branch name
-    divergent_branch = determine_divergent_branch(
-        rhel_version,
-        pp_api_url,
-        namespace,
-    )
+    divergent_branch = active_y - 1
     logger.debug("Divergent branch: {}".format(divergent_branch))
     
     g = gitpython.cmd.Git()
@@ -316,48 +311,6 @@ def does_divergent_branch_exist(repo_name, rhel_version, rhel_dist_git, pp_api_u
             raise
     return branch_exists
 
-def determine_divergent_branch(rhel_version, pp_api_url, namespace):
-    logger = logging.getLogger(__name__)
-
-    # Query the "package pages" API for the current active Y-stream release
-    # Phase 230 is "Planning / Development / Testing" (AKA DeveTestDoc)
-    request_params = {
-        "phase": 230,
-        "product__shortname": "rhel",
-        "relgroup__shortname": rhel_version,
-        "format": "json",
-    }
-
-    res = requests.get(
-        os.path.join(pp_api_url, "latest", "releases"),
-        params=request_params,
-        timeout=60,
-    )
-    res.raise_for_status()
-    payload = json.loads(res.text)
-    logger.debug(
-        "Response from PP API: {}".format(json.dumps(payload, indent=2))
-    )
-    if len(payload) < 1:
-        raise RuntimeError("Received zero potential release matches)")
-
-    active_y_version = -1
-    for entry in payload:
-        shortname = entry["shortname"]
-
-        # The shortname is in the form rhel-9-1.0
-        # Extract the active Y-stream version
-        m = re.search("(?<={}-)\d+(?=\.0)".format(rhel_version), shortname)
-        if not m:
-            raise RuntimeError(
-                "Could not determine active Y-stream version from shortname"
-            )
-        y_version = int(m.group(0))
-        if y_version > active_y_version:
-            active_y_version = y_version
-
-    # The divergent branch is Y-1
-    return "{}.{}.0".format(rhel_version, active_y_version - 1)
 
 def _datesplit(isodate):
     date_string_tuple = isodate.split('-')
@@ -372,9 +325,10 @@ def determine_active_y_version(rhel_version, pp_api_url):
     logger = logging.getLogger(__name__)
 
     # Query the "package pages" API for the current active Y-stream release
-    # Phase 230 is "Planning / Development / Testing" (AKA DeveTestDoc)
+    # Phase 230 is "Planning / Development / Testing" (AKA DevTestDoc)
+    # Phase 450 is "Stabilization"
     request_params = {
-        "phase": 230,
+        "phase__in": "230,450",
         "product__shortname": "rhel",
         "relgroup__shortname": rhel_version,
         "format": "json",
@@ -391,7 +345,7 @@ def determine_active_y_version(rhel_version, pp_api_url):
         "Response from PP API: {}".format(json.dumps(payload, indent=2))
     )
     if len(payload) < 1:
-        raise RuntimeError("Received zero potential release matches)")
+        raise RuntimeError("Received zero potential release matches")
 
     release_id = -1
     active_y_version = -1
@@ -410,26 +364,7 @@ def determine_active_y_version(rhel_version, pp_api_url):
             active_y_version = y_version
             release_id = entry["id"]
 
-    # Now look up whether we are in the Exception Phase for this Y-stream release
-    request_params = {
-        "name__regex": "(Excep|Stabiliza)tion Phase",
-        "format": "json",
-    }
-    res = requests.get(os.path.join(pp_api_url, "latest", "releases", str(release_id), "schedule-tasks"), params=request_params)
-    res.raise_for_status()
-    payload = json.loads(res.text)
-    logger.debug(
-        "Response from phase lookup: {}".format(json.dumps(payload, indent=2))
-    )
-
-    # This lookup *must* return exactly one value or the Product Pages are
-    # wrong and must be fixed.
-    assert len(payload) == 1
-
-    # Determine if this Y-stream release is in the exception phase
-    today = datetime.now(tz=pytz.utc).date()
-    exception_start_date = date(*_datesplit(payload[0]["date_start"]))
-    in_exception_phase = today >= exception_start_date
+        in_exception_phase = entry["phase"] == 450
 
     logger.debug("Active Y-stream: {}, Enforcing: {}".format(active_y_version, in_exception_phase))