AI API Congestion Calendar

DeepSeek's official support guidelines explicitly use a 'Server Busy' error state to mask cluster-wide capacity saturation. When the cluster hits peak load, the documented mitigation is to toggle off 'Deep Think' (R1) — reasoning models consume vastly more compute and hit the saturation first — and use the standard V3 model, which is allocated a separate, higher-capacity processing pool. DeepSeek's own concurrency limits (verified) are 500 for v4-pro and 2,500 for v4-flash. Specific peak-hour windows are not published — the visual blocks above illustrate global business-hour load.

Zhipu's official GLM developer documentation states that the platform applies a peak-hour quota multiplier: token usage is deducted at 3× the normal rate during the official 14:00–18:00 UTC+8 peak window (= 06:00–10:00 UTC) and 2× during other Asia daytime hours. Newer reasoning models (GLM-5.2, GLM-5-Turbo) are most affected. Concurrent requests are also hard-capped — even paid Max plans queue simultaneous workflows during peak.

Qwen API is integrated with Alibaba Cloud's broader infrastructure. Qwen does not document a fixed daily peak window — the verified impact is event-driven: during Double 11 (Singles' Day), Chinese New Year, and other Alibaba e-commerce events, model API quotas can drop up to ~70% for non-enterprise tiers as compute is re-allocated to retail search/recommendation workloads. The visual block above illustrates the event-driven nature, not a fixed clock-time pattern.

Moonshot's official Kimi Code + API documentation governs usage with a strict rolling 5-hour window plus weekly and monthly caps — when request frequency spikes during China high-traffic periods, rate limiting automatically freezes the quota until the 5-hour window rolls forward. Free tier (Tier 0) is hard-limited to 1 concurrent request + 3 RPM + 1.5M TPD, so any rapid clicking during errors exhausts the quota instantly. The visual windows above mirror the documented 09:00–22:00 CST peak.

No time-of-day congestion restrictions documented.

Mistral's La Plateforme API enforces per-second rate limits without a documented time-of-day quota multiplier. The visual block above does not imply specific peak windows — verified behaviour is per-second concurrency caps and 429 retries. On-premise self-hosted deployments are unaffected. Live uptime per surface area is published at the Mistral Status page (linked below).

Anthropic's official policy (r/Anthropic AMA, July 2025): tier-based rate limits PLUS a 5-hour rolling session window PLUS a weekly cap (Aug 28, 2025 onward) — Max 20x users get 240–480 weekly Sonnet 4 hours and 24–40 weekly Opus 4 hours. The 5-hour budget burns significantly faster during US business hours (5 AM–11 AM PT / 1 PM–7 PM GMT) when compute demand spikes — Anthropic frames this as 'limited compute during peak hours', not a per-hour quota multiplier. Anthropic uses a queue-based delay system for Sonnet rather than outright 429 rejections; Opus is often unavailable for lower-tier accounts during peak. Pro ($20) and Max ($100/$200) plans all expose these windows to the same peak-hour compression.

No time-of-day congestion restrictions documented.

Google's official Vertex AI documentation describes three PayGo tiers (Standard / Priority / Flex) and explicitly recommends that developers schedule token-heavy tasks and background workflows during off-peak hours and on weekends — Standard PayGo tiers experience heavily elevated throttling during high-demand daytime windows. Google AI Studio free tier is the first to throttle; Vertex AI paid tiers maintain guaranteed throughput. Gemini Flash models are less affected than Pro/Ultra at peak. The visual block above represents the documented baseline — no fixed clock-time peak is publicly published.

No time-of-day congestion restrictions documented.

Official OpenAI Help Center (help.openai.com/en/articles/11909943): ChatGPT Plus and ChatGPT Go subscribers get up to 160 messages per 3-hour window with base models (GPT-5.5) — after the threshold is hit, chats are silently switched to the 'mini' variant of the model until the window resets. Plus tier uses an adaptive 'smart throttle' that tightens the cap during global business hours when server load spikes; users hitting the threshold are also returned temporary 'too many requests' cooldowns. GPT-4o mini / o4-mini maintain higher quotas than full-size models during the same window. Tier-1 free-tier API keys face the steepest reduction (90%+) at peak. The visual block represents the documented rolling-3-hour cap — no fixed clock-time peak is published by OpenAI.

When is the best time to call the DeepSeek API to avoid rate limits?

DeepSeek's lowest-congestion window is roughly 22:00–11:00 UTC (overnight Asia through European morning). Avoid the 13:00–17:00 UTC wave when China daytime overlap US morning. DeepSeek's documented mitigation for the "Server Busy" state is to turn off "Deep Think" (R1) — reasoning requests hit the saturation first — and fall back to V3, which sits on a higher-capacity processing pool.

Why does OpenAI ChatGPT Plus silently downgrade me to a "mini" model?

ChatGPT Plus and ChatGPT Go are officially capped at 160 messages per 3-hour window with the base model (GPT-5.5). Once you cross that line, chats are silently switched to the model's "mini" variant until the window resets — this is an OpenAI Help Center feature, not a bug. The adaptive throttle tightens further during global business-hour load spikes. To preserve full-model access during crunch time, switch to API key billing or downgrade usage.

When does Anthropic Claude hit the "5-hour window" wall hardest?

Anthropic frames the rolling 5-hour session window in conjunction with a weekly cap (introduced 28 Aug 2025). Community observations and one specific 430-upvote complaint thread indicate the 5-hour budget burns significantly faster during US business hours, roughly 13:00–19:00 UTC (5–11 AM Pacific / 1–7 PM GMT). Anthropic frames this as limited compute during peak hours rather than a stated time-based multiplier. Max 20x users get 240–480 Sonnet 4 hours/week and 24–40 Opus 4 hours/week.

When does Zhipu's GLM apply its 3× peak-hour quota multiplier?

Zhipu's official GLM developer documentation states the platform applies a peak-hour token quota multiplier: usage is deducted at 3× normal rate during the official 14:00–18:00 UTC+8 window (≈ 06:00–10:00 UTC) and 2× during other Asia daytime hours. The flagship GLM-5.2 and GLM-5-Turbo reasoning models are the most affected. Concurrent request caps are additionally hard-limited even on Max paid plans.

How can I avoid AI provider throttling without changing providers?

Three reliable strategies: (1) batch off-peak — schedule large jobs in each provider's lowest-quota-multiplier window; (2) downshift the model — GPT-4o mini, Claude Haiku, Gemini Flash, and GLM Flash tiers are dramatically less throttled; (3) add retry-after jitter — respect the Retry-After response header and back off exponentially to avoid compounding the queue.