AdWords API v201506 will be sunset on April 11, 2016, after which all v201506 API requests will begin to fail. This version was deprecated on October 5, 2015. If you are still on v201506, we recommend that you migrate directly to v201601 and skip v201509. Please be sure to migrate prior to sunset to ensure your API access is unaffected.

We've prepared various resources to help you with the migration: As always, if you have any questions about this migration, please contact us via the forum or the Ads Developers Plus Page.