I was trying to figure out earlier today how to get 4.6 to run in Claude Code, as part of the output it included "- Still fully supported — not scheduled for retirement until Feb 2027." Full caveat of, I don't know where it came up with this information, but as others have said, 4.5 is still available today and it is now 5, almost 6 months old.

I'm still using 4.5 because it gets the niche work I'm using it for where 4.6 would just fight me.

Opus 4.5 is still available