EB Worker cron.yaml - is not authorized to perform: dynamodb:UpdateItem

I have been trying to implement a cron job on my EB worker.

My EB CLI on a deploy says "ERROR: Update environment operation is complete, but with errors."

My yaml seems to parse just fine and in my EB events list I see the line "Successfully loaded 1 scheduled tasks from cron.yaml."

version: 1
cron:
 - name: "cron"
   url: "/cron"
   schedule: "* * * * *"

I look in the eb-activity.log and there is this issue:

Activity execution failed, because: User: arn:aws:sts::550612933446:assumed-role/WorkerTierRole_KK/i-5fe79aa0 is not authorized to perform: dynamodb:UpdateItem on resource: arn:aws:dynamodb:us-east-1:550612933446:table/awseb-e-jcrjmidtsu-stack-AWSEBWorkerCronLeaderRegistry-1GVA6A4AV0YDW - (Aws::DynamoDB::Errors::AccessDeniedException) (ElasticBeanstalk::ExternalInvocationError)
caused by: User: arn:aws:sts::550612933446:assumed-role/WorkerTierRole_KK/i-5fe79aa0 is not authorized to perform: dynamodb:UpdateItem on resource: arn:aws:dynamodb:us-east-1:550612933446:table/awseb-e-jcrjmidtsu-stack-AWSEBWorkerCronLeaderRegistry-1GVA6A4AV0YDW - (Aws::DynamoDB::Errors::AccessDeniedException) (Executor::NonZeroExitStatus)

This is what I also found in the log:

2015-06-04T02:17:19Z schedule-parser: Successfully loaded 1 scheduled tasks from file /opt/python/current/app/cron.yaml .
2015-06-04T02:17:19Z init: User: arn:aws:sts::550612933446:assumed-role/WorkerTierRole_KK/i-254d00f5 is not authorized to perform: dynamodb:UpdateItem on resource: arn:aws:dynamodb:us-east-1:550612933446:table/awseb-e-jcrjmidtsu-stack-AWSEBWorkerCronLeaderRegistry-1KMJ9BLOVIUSJ (Aws::DynamoDB::Errors::AccessDeniedException)
    at /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/seahorse/client/plugins/raise_response_errors.rb:15:in `call'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/aws-sdk-core/plugins/dynamodb_simple_attributes.rb:112:in `call'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/seahorse/client/plugins/param_conversion.rb:22:in `call'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/aws-sdk-core/plugins/response_paging.rb:10:in `call'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/seahorse/client/request.rb:70:in `send_request'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sdk-core-2.0.10/lib/seahorse/client/base.rb:215:in `block (2 levels) in define_operation_methods'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/vendor/AWSMACLE/lib/leader_election/storage_manager.rb:81:in `update_registration'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/vendor/AWSMACLE/lib/leader_election/storage_manager.rb:19:in `verify_table'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/vendor/AWSMACLE/lib/leader_election/daemon.rb:37:in `initialize'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/vendor/AWSMACLE/lib/leader_election.rb:8:in `new'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/vendor/AWSMACLE/lib/leader_election.rb:8:in `create'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/lib/aws-sqsd/cron.rb:241:in `leader_election_daemon'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/lib/aws-sqsd/cron.rb:30:in `initialize'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/lib/aws-sqsd/daemon.rb:44:in `new'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/lib/aws-sqsd/daemon.rb:44:in `initialize'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/bin/aws-sqsd:34:in `new'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/bin/aws-sqsd:34:in `start'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/bin/aws-sqsd:83:in `launch'
    from /opt/elasticbeanstalk/lib/ruby/lib/ruby/gems/2.1.0/gems/aws-sqsd-2.0/bin/aws-sqsd:111:in `<top (required)>'
    from /opt/elasticbeanstalk/lib/ruby/bin/aws-sqsd:23:in `load'
    from /opt/elasticbeanstalk/lib/ruby/bin/aws-sqsd:23:in `<main>'

I have tried rebuilding my environment but that didn't make any difference.

It seems like this error is out of my hands (hope that is not the case and I have made a simple mistake) and is an EB issue with how it handles cron jobs. I don't have any dynamodb's :)

Many thanks for any help, Phil