Post PR #4559: add back `.dev1` to version numbers. (#4561)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 343c7fa..c92239c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,11 +8,22 @@
 
 - Upgrading `concurrent.futures` backport from `>= 3.0.0`
   to `>= 3.2.0` (#4521).
+- Moved `datetime`-related helpers from `google.cloud.core` to
+  `google.api_core.datetime_helpers` (#4399).
+- Added missing `client_info` to `gapic_v1/__init__.py`'s
+  `__all__` (#4567).
+- Added helpers for routing headers to `gapic_v1` (#4336).
+
+PyPI: https://pypi.org/project/google-api-core/0.1.2/
 
 ## 0.1.1
 
+### Dependencies
+
 - Upgrading `grpcio` dependency from `1.2.0, < 1.6dev` to `>= 1.7.0` (#4280)
 
+PyPI: https://pypi.org/project/google-api-core/0.1.1/
+
 ## 0.1.0
 
 Initial release
@@ -42,3 +53,5 @@
 - Port gax proto helper methods (#4249)
 - Remove gapic_v1.method.wrap_with_paging (#4257)
 - Add final set of protobuf helpers to api_core (#4259)
+
+PyPI: https://pypi.org/project/google-api-core/0.1.0/
diff --git a/setup.py b/setup.py
index d07393c..ede41b1 100644
--- a/setup.py
+++ b/setup.py
@@ -68,7 +68,7 @@
 
 setup(
     name='google-api-core',
-    version='0.1.2',
+    version='0.1.3.dev1',
     description='Core Google API Client Library',
     long_description=README,
     namespace_packages=['google'],