Hello,

Version 1.15 of Jenkins EC2 plugin was released couple of days ago. Appears to have generic fixes here and there, nothing which immediately would resolve our woes, but may help anyway:

https://wiki.jenkins-ci.org/display/JENKINS/Amazon+EC2+Plugin#AmazonEC2Plugi...

So, I'd like to propose spending time on Connect hacking sessions to test it (on sandbox) and upgrade production if all goes well.