diff --git a/.github/workflows/code.yml b/.github/workflows/code.yml
index 9fa2657f..51f84bd4 100644
--- a/.github/workflows/code.yml
+++ b/.github/workflows/code.yml
@@ -38,8 +38,7 @@ jobs:
       # https://github.com/davidslusser/actions_python_ruff/issues/2
 
       - run: pip install ruff
-      - run: | 
-        ruff check .
+      - run: ruff check .
   
   install-catalogs:
     name: Install & cache databroker catalogs
diff --git a/CHANGES.rst b/CHANGES.rst
index 2090d175..95b7b03c 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -24,7 +24,18 @@ describe future plans.
    1.6.20
    ******
 
-   release expected by 2024-04-30
+   release expected by 2024-07-19
+
+   New Features
+   ------------
+
+   * Add new APS PlanarUndulator device.
+
+   Maintenance
+   -----------
+
+   * Pin numpy<2 because upstream dask package needs a fix.
+   * Removed ApsUndulator and ApsUndulatorDual devices.
 
 1.6.19
 ******
@@ -34,8 +45,8 @@ released 2024-04-23
 New Features
 ------------
 
-* Add new plan for edge alignment called edge_align
-* Added a mesh grid scan plan that will collect until number of collection points is met
+* Add new plan for edge alignment called edge_align.
+* Added a mesh grid scan plan that will collect until number of collection points is met.
 
 Fixes
 -----
diff --git a/apstools/devices/aps_undulator.py b/apstools/devices/aps_undulator.py
index 0a62883b..6bbc2b0f 100644
--- a/apstools/devices/aps_undulator.py
+++ b/apstools/devices/aps_undulator.py
@@ -1,15 +1,13 @@
 """
-APS undulator
-+++++++++++++++++++++++++++++++++++++++
+APS undulators
+++++++++++++++
 
 .. autosummary::
 
-   ~ApsUndulator
-   ~ApsUndulatorDual
+   ~PlanarUndulator
 """
 
 import logging
-from enum import IntEnum
 
 from ophyd import Component
 from ophyd import DerivedSignal
@@ -17,26 +15,11 @@
 from ophyd import EpicsSignal
 from ophyd import EpicsSignalRO
 from ophyd import PVPositioner
-from ophyd import Signal
 
-from .tracking_signal import TrackingSignal
 
 logger = logging.getLogger(__name__)
 
-
-class DoneStatus(IntEnum):
-    MOVING = 0
-    DONE = 1
-
-
-class BusyStatus(IntEnum):
-    DONE = 0
-    BUSY = 1
-
-
-class MotorDriveStatus(IntEnum):
-    NOT_READY = 0
-    READY_TO_MOVE = 1
+POSITIONER_DONE = 1
 
 
 class UndulatorPositioner(PVPositioner):
@@ -53,7 +36,7 @@ class UndulatorPositioner(PVPositioner):
     actuate = Component(DerivedSignal, derived_from="parent.start_button", kind="omitted")
     stop_signal = Component(DerivedSignal, derived_from="parent.stop_button", kind="omitted")
     done = Component(DerivedSignal, derived_from="parent.done", kind="omitted")
-    done_value = DoneStatus.DONE
+    done_value = POSITIONER_DONE
 
 
 class PlanarUndulator(Device):
diff --git a/environment.yml b/environment.yml
index 540c23f9..bb08b278 100644
--- a/environment.yml
+++ b/environment.yml
@@ -18,6 +18,7 @@ dependencies:
   - intake <=1
   - matplotlib-base
   - mongoquery >=1.3.6
+  - numpy <2
   - openpyxl
   - ophyd >=1.6.1
   - pandas