As far as I can see, the ansible-core 2.19 roadmap hasn’t changed yet. I’m not sure if we should change any dates if we don’t have ones from core that we can point to.
Maybe start with an info box stating a delay because of and mentioning ansible-core 2.19 release schedule update?
At the very least, we should announce both here on the forum and on Bullhorn (maybe simply mentioning the forum post) that we will delay Ansible 12 because of the ansible-core 2.19 release schedule update.