Batch job with Multiple start conditions

Hi SAP Experts,

I am looking to schedule a batch with multiple start conditions.

Issue : Current Batch job is running on every 1 hours. due to volume of idocs, we could see many are failing to create delivery document and charging the customer.

Suggestion: So i am trying to create another batch job with on every 15 min. If the job is not finishing within 15 min then next job will pick the same IDOC and there is a possibility of double charging the customer.

Expectation: we should schdule the job on every 15 mins and also it should check the previous run if successful.

Please share your thoughts and help..

Thanks in advance.

Regards

Raja