6.0 Sol was literally a week ago... Basically continuous integration for model releases at this point.
Since Luna is so dirt cheap compared to Sol/Astra it would be nice if they could set or you could reserve some small percent like 3-5% of usage pool on codex just for Luna so if you hit usage limits you can at least still run a lot of Luna.
They do, when I was on the $20 plan, I got shown a Luna Reserve model which had its own dedicated quota.
As many have surmised, this may have been a panic rename of Astra 6.1
Interesting idea, but at the same time it is just so cheap that you can just run it with API pricing. I sometimes do even if I have available usage that I'm going to cap so I'll save it for bigger models