ebextensions no longer running on deploy or reboot under Ubuntu

I’m not super conversant in AWS, but know just enough to get myself into trouble…

I have a handful of .ebextensions configs that used to work (for a couple years) but appear to have stopped working in the past month or so. I have them setting the local time, yum installing the jdk, writing a cronjob sh file, and a few other very basic config tasks.

In the log, they are all “inflating…” to a temp holding directory but never run, as far as I can tell from scouring the logs. All of the other contents of the war file are successfully put where they are supposed to go. The configs are nowhere to be found (which I understand is expected behavior).

I deploy via the EB web interface, and can do so successfully. I have a Java servlets app running on Tomcat, and have confirmed that my .ebextensions directory is present at the top level of my war file, and that the configs are all compliant yaml.

Am hoping for suggestions on things to try. I have tried redeploying the app and rebooting the EC2 (Ubuntu) instance, and scrutinized the logs for any hint of what may being going wrong. No love so far.