diff --git a/subiquity/server/controllers/filesystem.py b/subiquity/server/controllers/filesystem.py
index 8c8bb021..45a60adf 100644
--- a/subiquity/server/controllers/filesystem.py
+++ b/subiquity/server/controllers/filesystem.py
@@ -211,8 +211,9 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
         await super().configured()
         self.stop_listening_udev()
 
-    async def _mount_systems_dir(self):
-        self._source_handler = self.app.controllers.Source.get_handler()
+    async def _mount_systems_dir(self, variation_name):
+        self._source_handler = \
+                self.app.controllers.Source.get_handler(variation_name)
         source_path = self._source_handler.setup()
         cur_systems_dir = '/var/lib/snapd/seed/systems'
         source_systems_dir = os.path.join(source_path, cur_systems_dir[1:])
@@ -234,9 +235,9 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
             self._source_handler.cleanup()
             self._source_handler = None
 
-    async def _get_system(self, label):
+    async def _get_system(self, variation_name, label):
         try:
-            await self._mount_systems_dir()
+            await self._mount_systems_dir(variation_name)
         except NoSnapdSystemsOnSource:
             return None
         try:
@@ -304,7 +305,7 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
             system = None
             label = variation.snapd_system_label
             if label is not None:
-                system = await self._get_system(label)
+                system = await self._get_system(name, label)
             log.debug("got system %s for variation %s", system, name)
             if system is not None and len(system.volumes) > 0:
                 self._variation_info[name] = self.info_for_system(
@@ -606,7 +607,7 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
     async def guided_core_boot(self, disk: Disk):
         # Formatting for a core boot classic system relies on some curtin
         # features that are only available with v2 partitioning.
-        await self._mount_systems_dir()
+        await self._mount_systems_dir(self._info.name)
         self.model.storage_version = 2
         [volume] = self._info.system.volumes.values()
         self._on_volume = snapdapi.OnVolume.from_volume(volume)
diff --git a/subiquity/server/controllers/tests/test_filesystem.py b/subiquity/server/controllers/tests/test_filesystem.py
index 9c5a87c7..51e4b10f 100644
--- a/subiquity/server/controllers/tests/test_filesystem.py
+++ b/subiquity/server/controllers/tests/test_filesystem.py
@@ -833,6 +833,7 @@ class TestCoreBootInstallMethods(IsolatedAsyncioTestCase):
         self.fsc = FilesystemController(app=self.app)
         self.fsc._configured = True
         self.fsc.model = make_model(Bootloader.UEFI)
+        self.fsc._mount_systems_dir = mock.AsyncMock()
 
     def _add_details_for_structures(self, structures):
         self.fsc._info = VariationInfo(