How to trigger concurrent builds in bamboo for two concurrent commits on github

[Manoj.Murali]

I have  two repos (r1 & r2) hooked into a bamboo plan, which has got two agents (a1 & a2) configured into it. configured the pipeline to trigger using remote trigger. So that when there is a commit on any repos configured, the pipeline gets triggerd. When there is a concurrent commit on each r1 and r2 with commit id (c1 & c2), bamboo results in building both the repos. 

Both r1 and r2 are configured to same buildkey (bk1) via a webhook (/updateAndBuild.action?buildKey=bk1).

My requirement is bamboo to trigger two different builds concurrently when there is a concurrent commits on both r1 and r2.

Is there anyway to achieve this.