After updating a Sandbox to Wave 2 2022 the new Advanced Find was there (and I used it), a day or two later it has disappeared.
If I go to settings and turn off the "new" Advanced Find the button reappears and gives me the old Advanced Find. If I toggle it back on again, the button disappears again.
Other Feedback would be that the new Advanced Find is not as good as the old, too many clicks and time involved to achieve the same result as the old Advanced Find