On Area 51, the proposal pages for Quantum Computing and Artificial Intelligence both say, "This site is in Public Beta".
However, the Home pages of Quantum Computing and Artificial Intelligence don't have the Site Stats sidebar that all Beta sites have. They also have distinctive topbars and colour schemes, and the site names in the topbar don't have the "Beta" logo next to them.
At first, I thought this was because these are/were sponsored sites, according to Which Stack Exchange sites have dedicated sponsors?. However, the Ask Patents and DevOps sites are/were also sponsored sites, and the former has a Site Stats sidebar along with having a distinctive topbar and theme and missing the Beta label in the site name, and the latter looks exactly like any other Beta site, including the Site Stats sidebar, theme, and Beta label in the site name.
What accounts for the differences between these sites? Have Quantum Computing and Artificial Intelligence graduated and their Area 51 pages not been updated for some reason?