well… that’s what a clean OH 2.1 stable release reports when installing the Astro 2.1 binding from PaperUI:
(openHAB2 console):
openhab> list -s |grep -i astro
207 | Active | 80 | 0.9.0.b5 | Astro Binding | org.eclipse.smarthome.binding.astro
Accessing remote repos for the bindings (not using the offline addons)