you can get testing release of PureOS 11 (Crimson), by modifying the Byzantium’s download link, if you want.
just delete anything after the “byzantium”, leaving only https://downloads.puri.sm/
Then you click “wip”, then “crimson”, and you can see a list of available flavours for you to download. Click here for express access. These are the newest builds, but is not quite the same as mature releases.
also, check this: