If you are referring to the final release, it should be released by the end of the year. If you are referring to the beta, the beta has not been released for the note 10 and there is no specific date. Once available you should see a registration option in the Samsung members app
It is at the US carriers now, Samsung told me today, it depends on what carrier someone have, which version phone you have and they release the update in batches, it should be here this month. He was not sure when, but this month. Different carriers have different apps on there phones and that suppose to matter. But soon.