THE MONTH IN FOUR LINES
● Confirmed: Claude Code weekly limits settle lower on 14 September.
● Targeted, not confirmed: an OpenAI public listing, filed confidentially 8 June.
● Indicated, no date: Grok 4.7, early to mid September per Musk. No model ID published.
● Already happened: Sonnet 5 repricing and the Codex model change landed 31 August.
Confirmed dates
| Date |
What changes |
Who it affects |
| 1 Sept |
John Ternus becomes Apple chief executive |
Nobody operationally, yet |
| 13 Sept |
Last day of the Claude Code 50 percent weekly boost |
Pro, Max, Team, seat-based Enterprise |
| 14 Sept |
Permanent weekly limits, 25 percent above the old baseline — 17 percent below current levels |
Anyone regularly above 83 percent on the weekly bar |
THE 14 SEPTEMBER ARITHMETIC
Index the pre-May standard at 100. Today is 150. From 14 September it is 125.
So it is 25 percent above the old baseline and 17 percent below what you have now — a figure Anthropic itself published after deleting its original announcement and reposting.
Targeted but unconfirmed
An OpenAI public listing. The company filed its S-1 confidentially on 8 June, targeting September. The public prospectus has still not appeared on EDGAR, and registration must be public at least 15 days before a roadshow — so each day without a filing narrows the window. Separately, the CFO told staff in August that OpenAI will be public in 2027, or sooner if the business continues to inflect. Those two statements are not contradictory, but they point at different months.
Grok 4.7. Musk indicated an early to mid September window. Pre-training is reported complete with supplemental training on SpaceX engineering data. There is still no model ID at docs.x.ai, no published price and no benchmark card. Do not plan a migration around it.
Anthropic's listing. Reported as targeting October after a confidential filing on 1 June. Worth tracking this month because the preparation is visible before the date is.
Already settled, but the effects land now
| Change |
What you will notice in September |
| Sonnet 5 at $3/$15 |
First full month at the new rate, plus a tokenizer change adding 10 to 35 percent tokens on code |
| GPT-5.4 gone from Codex |
Only for ChatGPT sign-in. API-key sessions still have it |
| kimi-k2.5 and moonshot-v1 sunset |
Anything still pointing at those model IDs fails now |
| DALL·E GPT retired |
ChatGPT Images is the replacement, on all tiers |
Beyond September
- 1 October — OpenAI vs Apple hearing on the trade secrets suit.
- 24 October — deepseek-chat and deepseek-reasoner deprecated.
- 12 November — OpenAI models leave Cursor following the SpaceX acquisition. Anthropic has not said whether Claude follows.
- Around 21 November — GPT-5.6 Sol promotional pricing ends, $4 and $20 returning to $5 and $30.
What to do in the first week
- Measure your Claude Code usage now, while the higher ceiling is still in place. You have until the 13th to learn where your real consumption sits.
- Recalculate September API spend at $3 and $15, then add the tokenizer increase if your input is mostly code.
- Grep for retired model IDs — gpt-5.4, kimi-k2.5, moonshot-v1. Anything still referencing them is already failing.
- Do not price anything against GPT-5.6 Sol at $4/$20. Use $5/$30, the rate that returns in November.
Sources
FAQ
What are the AI deadlines in September 2026?
The confirmed one is 14 September, when Claude Code weekly limits settle at 25 percent above the pre-May baseline, ending the 50 percent boost on the 13th. An OpenAI listing has been targeted for September since a confidential filing on 8 June but is unconfirmed, and Grok 4.7 sits in an indicated early-to-mid month window with no published model ID.
Are Claude Code limits going up or down on 14 September?
Up 25 percent against the pre-May standard, down 17 percent against current levels. Anthropic published the second figure itself.
Is the OpenAI IPO happening this month?
Unconfirmed. The confidential S-1 was filed on 8 June targeting September, the public prospectus has not appeared on EDGAR, and registration must be public at least 15 days before a roadshow. The CFO separately told staff the company will be public in 2027 or sooner.
When is Grok 4.7 released?
No date. Musk indicated early to mid September, pre-training is reported complete, and there is still no model ID, price or benchmark card published.
What already changed on 31 August?
Claude Sonnet 5 API pricing rose to $3 and $15 per million with a tokenizer change, GPT-5.4 and GPT-5.4 mini left Codex for ChatGPT sign-in users, and kimi-k2.5 and moonshot-v1 sunset.