Multiple beta testers have confirmed support for the feature but there are reports that the release is being rolled out publicly as well. The launch was first spotted by reddit user koukougr.
Today I found that my 2 welcome cameras where updated to support HomeKit Secure Video. My [Presence] still not supporting it.
Unlike the Logitech Circle 2, the Netatmo implementation of Secure Video still allows users to access the camera via the Netatmo app.