What above post said.
What I interpreted from site is that once it's 2/6, you can level up your level 10 ring to tradable (waste), or you can level up your level 9 ring **AND** make it tradable simultaneously. It's just like last event. And the event before that.
You can either level a 10 ring to tradable or make a level 9 ring level 10 AND tradable on last day. So if your ring is level 9 now, I think you should skip today and wait until tomorrow.
They said this:"When the box turns into a potion, return to Gaga and ask for an upgrade to increase the ring by 1 level **and** to make it tradable, or just to make it tradable if it's already at level 10."