I've recently taken a look at Elasticsearch and the Amazon OpenSearch fork.
Since the ES and kibana packages has been orphaned on 7.10.1 for a while I've adopted and bumped them to 7.10.2, which is the last version before the license change. Doing so required switching to jdk11 and the included gradle wrapper for builds (if someone wants to maintain gradle6 in community, feel free to contact me about it).
I'm going to keep it on <7.11.0 for now so we can provide a FOSS version, which means the beats package should stay on 7.10.2 as well for compatibility reasons. That will change when we push OpenSearch (including it's plugins and OpenSearch Dashboards) to community, since this gives users a FOSS alternative.
The reasons for why I don't package OpenSearch right now is that OpenSearch plugins currently can't be installed using the plugin manager and are a PITA to build  until the build-tools and other dependencies are published to Maven Central .
Best Regards hashworks