Presently AR jobs take between 8-10 hours to complete and these jobs are triggered every day even when no new changes are available in the upstream projects. A more efficient way to would be to design an upstream job which does the following before triggering AR job:

1. Check for submodule updates for new changes
2. Check submodule updates for (the previous job/day) AR job (or last successful run)
3. Check AR build status of the previous build 

[1.] https://jenkins.opendaylight.org/releng/view/autorelease/