Claude Opus 5.5 starts a new family, and OpenAI adds GPT-6 Sol and Luna
Week of September 21, 2026Prepared October 11, 20262 items
On September 22, Anthropic released Claude Opus 5.5, the first model in its Claude 5.5 family, with lower developer prices and higher usage limits on paid plans. The same day, OpenAI added two faster, more affordable models, GPT-6 Sol and GPT-6 Luna, to the GPT-6 family it began with GPT-6 Astra on September 3.
What to do this week
Two big releases on one day can make it feel as if everything needs comparing at once. It doesn’t. Choose one or two tasks you do every week, write down what a good result looks like, and test only those. Prices in this edition are list prices from the announcements and can change.
AnthropicNew modelAnnounced September 22, 2026
Anthropic releases Claude Opus 5.5, the first model in its Claude 5.5 family
What changed
Anthropic says Opus 5.5 “performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5,” generates output more than 30% faster than Opus 5, and “communicates more naturally than prior models.” Developer list prices are $4 per million input tokens and $20 per million output tokens, 20% less than Opus 5. Anthropic said Sonnet 5.5 and Haiku 5.5 would follow in the coming weeks; they were released on September 28 and October 7.
Who can use it
Available on all platforms, including Amazon Web Services, Google Cloud, and Microsoft Azure, and on the Claude Platform as claude-opus-5-5. Anthropic also raised five-hour usage limits on Pro, Max, Team, and seat-based Enterprise plans.
For church offices
Higher usage limits help staff who work through long documents, such as summarizing a vendor proposal for the board. Try it on one long write-up and check whether the key costs and dates come first.
For businesses
Anthropic says it leads its benchmarks in agentic coding, computer use, and knowledge work. Compare it with your current tool on one recurring report before switching.
Try this: Choose one recurring write-up where the main point tends to get buried, and run the same request through Opus 5.5 and your current model.
OpenAI adds GPT-6 Sol and GPT-6 Luna to its GPT-6 family
What changed
OpenAI added GPT-6 Sol and GPT-6 Luna, which it trained “with similar methods as GPT-6 Astra” to bring Astra’s advances to “faster, more affordable models.” OpenAI released Astra on September 3 and calls it “the world’s most intelligent and aligned model.” OpenAI says Sol “can take on difficult work tasks while giving you more room to iterate with higher usage limits and lower cost.” API list prices per million tokens are $2 input and $10 output for Sol, and $0.10 input and $0.50 output for Luna, compared with $10 and $50 for Astra.
Who can use it
Both models are in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise, and Edu users, and Free and Go users can use Luna in the desktop app. Neither was in the Chat tab at launch; GPT-6 began reaching the Chat tab on October 7. Developers can use them in the API as gpt-6-sol and gpt-6-luna.
For church offices
A church office on a Free or Go plan can try Luna in the desktop app for routine drafts, such as event reminders, and review each one before it goes out.
For businesses
A small team could try Sol on proposal drafts and Luna on routine sorting, then keep whichever gives acceptable results at the lower cost.
Try this: If you use ChatGPT Work or Codex, run one task you know well through Sol or Luna and compare it with a result you already trust.
OpenAI Research: Release (opens in a new tab)OpenAI, published September 22, 2026. Checked October 11, 2026. Lists “Introducing GPT-6 Sol and Luna” on September 22, 2026, and “GPT-6 Astra: A new generation of intelligence” on September 3, 2026.
